Table of Contents

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13A-16 OR 15D-16

OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended September 30, 2015

Commission File Number: 001-35866

KNOT OFFSHORE PARTNERS LP

(Translation of registrant’s name into English)

2 Queen’s Cross,

Aberdeen, Aberdeenshire

AB15 4YB

United Kingdom

(Address of principal executive office)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F   x             Form 40-F   ¨

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1):

Yes   ¨             No    x

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7):

Yes   ¨             No    x

Table of Contents

KNOT OFFSHORE PARTNERS LP

REPORT ON FORM 6-K FOR THE QUARTERLY PERIOD ENDED SEPTEMBER 30, 2015

Table of Contents

THIS REPORT ON FORM 6-K IS HEREBY INCORPORATED BY REFERENCE INTO THE REGISTRATION STATEMENT ON FORM F-3 (NO. 333-195976) ORIGINALLY FILED WITH THE SEC ON MAY 15, 2014.

2

Table of Contents

The accompanying notes are an integral part of the unaudited condensed consolidated and combined carve-out interim financial statements.  

3

Table of Contents

The accompanying notes are an integral part of the unaudited condensed consolidated and combined carve-out interim financial statements.

4

Table of Contents

The accompanying notes are an integral part of the unaudited condensed consolidated and combined carve-out interim financial statements.

5

Table of Contents

The accompanying notes are an integral part of the unaudited condensed consolidated and combined carve-out interim financial statements.

6

Table of Contents

The accompanying notes are an integral part of the unaudited condensed consolidated and combined carve-out interim financial statements.

7

Table of Contents

KNOT OFFSHORE PARTNERS LP

Notes to Unaudited Condensed Consolidated and Combined Carve-Out Financial Statements

1) Description of Business

KNOT Offshore Partners LP (the “Partnership”) is a publicly traded Marshall Islands limited partnership initially formed for the purpose of acquiring 100% ownership interests in four shuttle tankers owned by Knutsen NYK Offshore Tankers AS (“KNOT”) in connection with the Partnership’s initial public offering of common units (the “IPO”) which was completed in April 2013.

As of September 30, 2015, the Partnership had a fleet of nine shuttle tankers, the Windsor Knutsen , the Bodil Knutsen , the Recife Knutsen , the Fortaleza Knutsen , the Carmen Knutsen, the Hilda Knutsen, the Torill Knutsen , the Dan Cisne , and the Dan Sabia, each referred to as a “Vessel” and, collectively, as the “Vessels.” The Vessels operate under fixed long-term charter contracts to charterers, except for the Windsor Knutsen as of September 30, 2015 . In April 2014, the Partnership was notified that BG Group Plc (“BG Group”) would not exercise its option to extend the Windsor Knutsen time charter after the expiration of its initial term. In July 2014, the vessel was re-delivered. In June 2014, the Partnership entered into a new two-year time charter contract, which was subsequently amended in June 2015, with BG Group for the Windsor Knutsen. On October 13, 2015, the Windsor Knutsen commenced on the two-year time charter contract with BG Group. The time charter with BG Group has six one-year extension options. Prior to the commencement of its time charter with BG Group, the Windsor Knutsen was employed under a time-charter with KNOT. The time charter for the Bodil Knutsen expires in 2017 and contains customer options for extension through 2019. The Recife Knutsen and the Fortaleza Knutsen are under bareboat charter contracts that expire in 2023. The time charter for the Carmen Knutsen expires in 2023 and contains customer options for extension through 2026. The time charters for the Hilda Knutsen and the Torill Knutsen each expire in 2018 and contain a customer option for extension through 2023. The Dan Cisne and the Dan Sabia are under bareboat charter contracts that expire in 2023 and 2024, respectively.

2) Summary of Significant Accounting Policies

(a) Basis of Preparation

The accompanying unaudited condensed consolidated and combined carve-out financial statements are prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”) and applicable rules and regulations of the U.S. Securities and Exchange Commission (the “SEC”) for interim financial information. All intercompany balances and transactions are eliminated. The unaudited condensed consolidated and combined carve-out financial statements do not include all the disclosures and information required for a complete set of annual financial statements; and, therefore, these unaudited condensed consolidated and combined carve-out financial statements should be read in conjunction with the audited consolidated and combined carve-out financial statements for the year ended December 31, 2014, which are included in the Partnership’s Annual Report on Form 20-F (the “20-F”).

Under the Partnership’s First Amended and Restated Agreement of Limited Partnership (the “Partnership Agreement”), KNOT Offshore Partners GP LLC, a wholly owned subsidiary of KNOT, and the general partner of the Partnership (the “General Partner”), has irrevocably delegated to the Partnership’s board of directors the power to oversee and direct the operations of, manage and determine the strategies and policies of the Partnership. During the period from the Partnership’s IPO in April 2013 until the time of the Partnership’s first annual general meeting (“AGM”) on June 25, 2013, the General Partner retained the sole power to appoint, remove and replace all members of the Partnership’s board of directors. From the first AGM, four of the seven board members became electable by the common unitholders and accordingly, from this date, KNOT, as the owner of the General Partner, no longer retains the power to control the Partnership’s board of directors and, hence, the Partnership. As a result, the Partnership is no longer considered to be under common control with KNOT and as a consequence, the Partnership will not account for any vessel acquisitions from KNOT after June 25, 2013 as a transfer of equity interests between entities under common control.

In June 2014, December 2014, and June 2015, the Partnership acquired from KNOT a 100% interest in the subsidiaries that own and operate the Hilda Knutsen and the Torill Knutsen, the Dan Cisne, and the Dan Sabia , respectively. Accordingly, the results of these acquisitions are consolidated into the Partnership’s results from the respective dates of their acquisition. The Partnership accounted for these acquisitions as an acquisition of a business.

(b) Significant accounting policies

The accounting policies adopted in the preparation of the unaudited condensed consolidated and combined carve-out interim financial statements are consistent with those followed in the preparation of the Partnership’s audited consolidated and combined carve-out financial statements for the year ended December 31, 2014, as contained in the Partnership’s 20-F.

8

Table of Contents

(c) Accounting pronouncement not yet adopted

In May 2014, the Financial Accounting Standards Board (or FASB) and the International Accounting Standards Board (IASB) issued a comprehensive revenue recognition standard that will supersede existing revenue guidance under US GAAP and IFRS, Accounting Standards Update 2014-09, Revenue from Contracts with Customers , (or ASU 2014-09) for U.S. GAAP. ASU 2014-09 will require an entity to recognize revenue when it transfers promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. This update creates a five-step model that requires an entity to exercise judgment when considering the terms of the contract(s) which include (i) identifying the contract(s) with the customer, (ii) identifying the separate performance obligations in the contract, (iii) determining the transaction price, (iv) allocating the transaction price to the separate performance obligations, and (v) recognizing revenue when each performance obligation is satisfied. In August 2015, FASB issued an ASU (ASU 2015-14) to defer by one year the effective dates of its new revenue recognition standard for public and non-public entities reporting under US GAAP. As a result, the standard (ASU 2014-09) will be effective for public entities for annual reporting periods beginning after December 15, 2017 (2018 for calendar-year public entities) and interim periods therein. ASU 2014-09 shall be applied retrospectively to each period presented or as a cumulative-effect adjustment as of the date of adoption. Early adoption is not permitted under U.S. GAAP. The Partnership is evaluating the effect of adopting this new accounting guidance.

In August 2014, FASB issued Presentation of Financial Statements – Going Concern (Subtopic 205-40), Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern (ASU 2014-15). ASU 2014-15 requires management to evaluate whether there are conditions and events that raise substantial doubt about the entity’s ability to continue as a going concern within one year after the financial statements are issued (or available to be issued when applicable) and, if so, disclose that fact. Management will be required to make this evaluation for both annual and interim reporting periods, if applicable. Management also is required to evaluate and disclose whether its plans alleviate that doubt. The standard is effective for annual periods after December 15, 2016 and interim periods within annual periods beginning after December 15, 2016. Early adoption is permitted. The Partnership is evaluating the effect of adopting this new accounting guidance. The Partnership does not expect the adoption of this standard to have a material impact on the consolidated and combined financial statements.

In April 2015, the FASB issued ASU 2015-03, Interest – Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs . ASU 2015-03 requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. For KNOT Offshore Partners LP as a public business entity, the guidance is effective for annual and interim periods beginning after 15 December 2015. Early adoption is permitted. The Partnership has not yet adopted ASU 2015-03, Interest – Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs. The adoption of the new standard will have an impact on the balance sheets and reduce total assets and total liabilities. Also the implementation will be applied retrospectively.

3) Segment Information

The Partnership has not presented segment information as it considers its operations to occur in one reportable segment, the shuttle tanker market. As of September 30, 2015, the Partnership’s fleet consisted of nine vessels and operated under five time charters and four bareboat charters. As of September 30, 2014, the Partnership’s fleet consisted of seven vessels and operated under five time charters and two bareboat charters. Under the time charters and bareboat charters, the charterer, not the Partnership, controls the choice of which trading areas the applicable Vessel will serve. Accordingly, the Partnership’s management, including the chief operating decision makers, does not evaluate performance according to geographical region.

The following table presents revenues and percentage of consolidated and combined revenues for customers that accounted for more than 10% of the Partnership’s consolidated and combined revenues during the nine months ended September 30, 2015 and 2014. All of these customers are subsidiaries of major international oil companies, except KNOT, which was chartering the Windsor Knutsen until she was redelivered to BG Group in October, 2015.

9

Table of Contents

4) Goodwill Impairment Charge

During the three months ended June 30, 2015, the Partnership concluded that indicators of impairment were present due to a significant reduction in the price of the Partnership’s common units during the past few months. Consequently, the Partnership performed an interim vessel and goodwill impairment analysis as of June 30, 2015 on its fleet, concluding that there was no impairment to the vessels’ values. However, the Partnership determined that the carrying value of the goodwill exceeded its fair value. The impairment charge relates mainly to capitalized goodwill which arose in 2008 when the Partnership’s predecessor acquired the Windsor Knutsen and three other vessels then under construction, in a transaction that was then accounted for as a step transaction. As a result, a goodwill impairment charge of $6.2 million was recognized in the condensed consolidated and combined carve-out financial statements for the three and six months ended June 30, 2015. The fair value was determined using the present value of the expected future cash flows discounted at a rate equivalent to a market participant’s weighed average cost of capital. The estimates and assumptions regarding expected future cash flows and appropriate discount rates are in part based upon existing contracts, future shuttle tanker rates, historical experience, financial forecasts and industry trends and conditions. This non-cash impairment charge, which does not affect the Partnership’s operations, cash flows, liquidity, or any of its loan covenants, reduced the Partnership’s remaining goodwill balance to zero as of June 30, 2015, and which is also the balance as of September 30, 2015.

5) Derivative Instruments

The unaudited condensed consolidated and combined carve-out financial statements include the results of interest rate swap contracts to manage the Partnership’s exposure related to changes in interest rates on its variable rate debt instruments and the results of foreign exchange forward contracts to manage its exposure related to changes in currency exchange rates on its operating expenses, mainly crew expenses, in currency other than U.S. Dollars and on its contract obligations. The Partnership does not apply hedge accounting for derivative instruments. The Partnership does not speculate using derivative instruments.

By using derivative financial instruments to economically hedge exposures to changes in interest rates, the Partnership exposes itself to credit risk and market risk. Derivative instruments that economically hedge exposures are used for risk management purposes, but these instruments are not designated as hedges for accounting purposes. Credit risk is the failure of the counterparty to perform under the terms of the derivative instrument. When the fair value of a derivative instrument is positive, the counterparty owes the Partnership, which creates credit risk for the Partnership. When the fair value of a derivative instrument is negative, the Partnership owes the counterparty, and, therefore, the Partnership is not exposed to the counterparty’s credit risk in those circumstances. The Partnership minimizes counterparty credit risk in derivative instruments by entering into transactions with major banking and financial institutions. The derivative instruments entered into by the Partnership do not contain credit risk-related contingent features. The Partnership has not entered into master netting agreements with the counterparties to its derivative financial instrument contracts.

Market risk is the adverse effect on the value of a derivative instrument that results from a change in interest rates, currency exchange rates or commodity prices. The market risk associated with interest rate contracts is managed by establishing and monitoring parameters that limit the types and degree of market risk that may be undertaken.

The Partnership assesses interest rate risk by monitoring changes in interest rate exposures that may adversely impact expected future cash flows and by evaluating economical hedging opportunities.

The Partnership has historically used variable interest rate mortgage debt to finance its vessel construction or conversions. The variable interest rate mortgage debt obligations expose the Partnership to variability in interest payments due to changes in interest rates. The Partnership believes that it is prudent to limit the variability of a portion of its interest payments. To meet this objective, the Partnership entered

10

Table of Contents

into London Interbank Offered Rate (“LIBOR”)-based interest rate swap contracts to manage fluctuations in cash flows resulting from changes in the benchmark interest rate of LIBOR. These swaps change the variable rate cash flow exposure on the mortgage debt obligations to fixed cash flows. Under the terms of the interest rate swap contracts, the Partnership receives LIBOR-based variable interest rate payments and makes fixed interest rate payments, thereby creating the equivalent of fixed rate debt for the notional amount of its debt hedged.

As of September 30, 2015, the Partnership had entered into various interest swap agreements for a total notional amount of $412.3 million to hedge against the interest rate risks of its variable rate borrowings. Under the terms of the interest rate swap agreements, the Partnership receives interest based on three or nine month LIBOR and pays a weighted average interest rate of 1.55%.

As of September 30, 2015 and December 2014, the total notional amount of the Partnership’s outstanding interest rate swap contracts that were entered into in order to hedge outstanding or forecasted debt obligations were $412.3 million and $382.3 million, respectively. As of September 30, 2015 and December 31, 2014, the carrying amount of the interest rate swaps contracts were net liabilities of $8.4 million and $1.7 million, respectively. See Note 6 —Fair Value Measurements.

Changes in the fair value of interest rate swap contracts are reported in realized and unrealized gain (loss) on derivative instruments in the same period in which the related interest affects earnings.

The Partnership and its subsidiaries utilize the U.S. Dollar as their functional and reporting currency, because all of their revenues and the majority of their expenditures, including the majority of their investments in 9 vessels and their financing transactions, are denominated in U.S. Dollars. The Partnership’s predecessor also from time to time contracted vessels with contractual obligations to pay the yards in currencies other than the U.S. Dollar. Payment obligations in currencies other than the U.S. Dollar, and in particular operating expenses in Norwegian Kroner (NOK), expose the Partnership to variability in currency exchange rates. The Partnership believes that it is prudent to limit the variability of a portion of its currency exchange exposure. To meet this objective, the Partnership entered into foreign exchange forward contracts to manage fluctuations in cash flows resulting from changes in the exchange rates towards the U.S. Dollar. The agreements change the variable exchange rate to fixed exchange rates at agreed dates.

As of September 30, 2015 and December 31, 2014, the total contract amount in foreign currency of the Partnership’s outstanding foreign exchange forward contracts that were entered into to economically hedge outstanding future payments in currencies other than the U.S. Dollar were NOK 194.8 million and NOK 127.9 million, respectively. As of September 30, 2015 and December 31, 2014, the carrying amount of the Partnership’s foreign exchange forward contracts was a liability of $2.1 million and $2.7 million, respectively. See Note 6 —Fair Value Measurements.

The following table presents the realized and unrealized gains and losses that are recognized in earnings as net gain (loss) on derivative instruments for the three and nine months ended September 30, 2015 and 2014:

(a) Fair Value of Financial Instruments

The following table presents the carrying amounts and estimated fair values of the Partnership’s financial instruments as of September 30, 2015 and December 31, 2014. Fair value is defined as the amount that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date.

11

Table of Contents

The carrying amounts shown in the table above are included in the consolidated and combined carve-out balance sheets under the indicated captions. The carrying value of trade accounts receivable, trade accounts payable and receivables/payables to owners and affiliates approximate their fair value.

The fair values of the financial instruments shown in the above table as of September 30, 2015 and December 31, 2014 represent the amounts that would be received to sell those assets or that would be paid to transfer those liabilities in an orderly transaction between market participants at that date. Those fair value measurements maximize the use of observable inputs. However, in situations where there is little, if any, market activity for the asset or liability at the measurement date, the fair value measurement reflects the Partnership’s own judgment about the assumptions that market participants would use in pricing the asset or liability. Those judgments are developed by the Partnership based on the best information available in the circumstances, including expected cash flows, appropriately risk-adjusted discount rates and available observable and unobservable inputs.

The following methods and assumptions were used to estimate the fair value of each class of financial instruments:

(b) Fair Value Hierarchy

The following table presents the placement in the fair value hierarchy of assets and liabilities that are measured at fair value on a recurring basis (including items that are required to be measured at fair value or for which fair value is required to be disclosed) as of September 30, 2015 and December 31, 2014:

12

Table of Contents

The Partnership’s accounting policy is to recognize transfers between levels of the fair value hierarchy on the date of the event or change in circumstances that caused the transfer. There were no transfers into or out of Level 1, Level 2 or Level 3 as of September 30, 2015 and December 31, 2014

13

Table of Contents

7) Long-Term Debt

As of September 30, 2015 and December 31, 2014, the Partnership had the following debt amounts outstanding:

The Partnership’s outstanding debt of $610.3 million as of September 30, 2015 is repayable as follows:

As of September 30, 2015, the interest rates on the Partnership’s loan agreements were LIBOR plus a fixed margin ranging from 2.125% to 2.5%.

In June 2014, the Partnership’s subsidiaries KNOT Shuttle Tankers 18 AS, KNOT Shuttle Tankers 17 AS and Knutsen Shuttle Tankers 13 AS entered into a senior secured loan facility in an aggregate amount of $240 million (the “Senior Secured Loan Facility”). The Senior Secured Loan Facility consists of (i) a $220 million term loan (the “Term Loan Facility”) and (ii) a $20 million revolving credit facility (the “Revolving Credit Facility”). The Revolving Credit Facility was undrawn as of September 30, 2015. In June 2014, the Partnership’s subsidiary Knutsen Shuttle Tankers XII KS entered into a senior secured loan facility in the amount of $140 million (the “New Fortaleza and Recife Facility”). The New Fortaleza and Recife Facility was drawn in November 2014. The $117 million secured loan facility (the “Hilda Facility”) was entered into in 2011 in connection with financing the building of Hilda Knutsen . In connection with the Partnership’s acquisition of Knutsen Shuttle Tankers 14 AS, the company that owns the Hilda Knutsen , on June 30, 2014, the Hilda Facility was amended prior to the acquisition. The $117 million secured loan facility (the “Torill Facility”) was entered into in 2011 in connection with financing the building of Torill Knutsen . In connection with the Partnership’s acquisition of Knutsen Shuttle Tankers 15 AS, the company that owns the Torill Knutsen , on June 30, 2014, the Torill Facility was amended prior to the acquisition. In April 2014, KNOT’s subsidiaries owning the Dan Cisne and Dan Sabia , as the borrowers, entered into a $172.5 million senior secured loan facility in connection with the purchase of the vessels from J. Lauritzen. In connection with the Partnership’s acquisition of KNOT Shuttle Tankers 20 AS, the company that owns the Dan Cisne , in December 2014, the $172.5 million senior secured loan facility was split into a tranche related to the Dan Cisne (the “Dan Cisne Facility”) and a tranche related to Dan Sabia (the “Dan Sabia Facility”) and the Dan Cisne Facility was amended. In connection with the Partnership’s acquisition of KNOT Shuttle Tankers 21 AS, the company that owns the Dan Sabia , in June 2015, the Dan Sabia Facility was amended.

14

Table of Contents

In connection with the June 2015 Offering (see Note 13), the Partnership used a part of the net proceeds to repay the $20.0 million revolving credit facility, the $12.0 million Seller’s Credit provided by KNOT in connection with the acquisition of the Dan Cisne and $7.5 million of the Dan Sabia Facility.

The Partnership and KNOT Shuttle Tankers AS have guaranteed the facilities listed above. As of September 30, 2015, the Borrowers and the Partnership were in compliance with all covenants under the facilities listed above.

8) Income Taxes

Components of Current and Deferred Tax Expense

After the reorganization of the Partnership’s predecessor’s activities into the new group structure in February 2013, all profit from continuing operations in Norway is taxable within the Norwegian Tonnage Tax regime (“the tonnage tax regime”). The consequence of the reorganization was a one-time entrance tax into the tonnage tax regime due to the Partnership’s acquisition of the shares in the subsidiary that owns the Fortaleza Knutsen and the Recife Knutsen . Under the tonnage tax regime, the tax is based on the tonnage of the vessel and operating income is tax free. The net financial income and expense remains taxable as ordinary income tax for entities subject to the tonnage tax regime. For the portion of activities subject to the tonnage tax regime, tonnage taxes are classified as vessel operating expenses while the current and deferred taxes arising on net financial income and expense are reflected as income tax expense in the consolidated and combined carve-out financial statements.

The total amount of the entrance tax was estimated to be approximately $3.0 million, which was recognized in the three months ended March 31, 2013. The entrance tax is payable over several years and is calculated by multiplying the tax rate by the declining balance of the gain, which will decline by 20% each year. The amount payable will be affected by the change in tax rate which was reduced to 27 % in 2014 from 28 % in 2013 and the fluctuation in currency rates. Approximately $0.6 million of the estimated entrance tax was paid during 2014 and $0.2 and $0.1 million was paid during the first and second quarter of 2015, respectively. UK income tax is presented as income taxes payable, while $1.3 million is presented as non-current deferred taxes payable. Profit and loss from continuing operation before income taxes was taxable to Norway and significant components of current and deferred income tax expense attributable to income from continuing operations for the three months ended September 30, 2015 and 2014 as follows:

A valuation allowance for deferred tax assets is recorded when it is more likely than not that some of or all of the benefit from the deferred tax assets will not be realized. The valuation allowances relate to the financial loss carry forwards and other deferred tax assets for tonnage tax that, in the judgment of the Partnership, are more-likely-than not to be realized reflecting the Partnership’s cumulative loss position for tonnage tax. In assessing the realizability of deferred tax assets, the Partnership considers whether it is more-likely-than-not that some portion or all of the deferred tax assets will not be realized taking into account all the positive and negative evidence available, and there are no deferred tax assets recognized as of September 30, 2015 and December 31, 2014.

15

Table of Contents

9) Related Party Transactions

(a) Related Parties

Net expenses (income) from related parties included in the unaudited condensed consolidated and combined carve-out statements of operations for the three and nine months ended September 30, 2015 and 2014 are as follows:

(b) Guarantees and Indemnifications

Pursuant to the Omnibus Agreement, KNOT agreed to guarantee the payments of the hire rate under the initial charters of each of the Bodil Knutsen and the Windsor Knutsen for a period of five years from the closing date of the IPO.

In April 2014, the Partnership was notified that BG Group would not exercise its option to extend the Windsor Knutsen time charter after the expiration of its initial term. The vessel was re-delivered on July 28, 2014. In order to comply with its obligations under the Omnibus Agreement, on July 29, 2014, KNOT and the Partnership entered into a time charter for the vessel at a rate of hire that would have been in effect during the option period under the previous BG Group time charter. This charter will be effective until the new BG Group time charter commenced in October, 2015.

Under the Omnibus Agreement, KNOT has agreed to indemnify the Partnership until April 15, 2018, against certain environmental and toxic tort liabilities with respect to certain assets that KNOT contributed or sold to the Partnership to the extent arising prior to the time they were contributed or sold. However, claims are subject to a deductible of $0.5 million and an aggregate cap of $5 million.

16

Table of Contents

In addition, pursuant to the Omnibus Agreement, KNOT agreed to indemnify the Partnership for any defects in title to certain assets contributed or sold to the Partnership and any failure to obtain, prior to April 15, 2013, certain consents and permits necessary to conduct the Partnership’s business, which liabilities arise within three years after the closing of the IPO on April 15, 2013.

(c) Transactions with Management and Directors

See Note 9(a) for a discussion of the allocation principles for KNOT’s administrative costs, including management and administrative staff, included in the consolidated and combined carve-out statements of operations.

(d) Amounts Due from (to) Related Parties

Balances with related parties consisted of the following:

Amounts due from (to) related parties are unsecured and intended to be settled in the ordinary course of business. They primarily relate to vessel management and other fees due to KNOT and KOAS.

(e) Trade accounts payables

Trade accounts payables to related parties are included in total trade accounts payables in the balance sheet. The balances to related parties consisted of the following:

Assets Pledged

As of September 30, 2015 and December 31, 2014, Vessels with a book value of $1,091 million and $1,022 million, respectively, were pledged as security held as guarantee for the Partnership’s long-term debt and interest rate swap obligations. See Note 5 —Derivative Instruments and Note 7 —Long-Term Debt.

Claims and Legal Proceedings

From time to time, the Partnership is involved in various claims and legal actions arising in the ordinary course of business. In the opinion of management, the ultimate disposition of these matters will not have a material adverse effect on the consolidated and combined carve-out financial position, results of operations or cash flows.

17

Table of Contents

Insurance

The Partnership maintains insurance on all the Vessels to insure against marine and war risks, which include damage to or total loss of the Vessels, subject to deductible amounts that average $0.150 million per Vessel, and loss of hire.

Under the loss of hire policies, the insurer will pay a compensation for the lost hire rate agreed in respect of each Vessel for each day, in excess of 14 deductible days, for the time that the Vessel is out of service as a result of damage, for a maximum of 180 days. In addition, the Partnership maintains protection and indemnity insurance, which covers third-party legal liabilities arising in connection with the Vessels’ activities, including, among other things, the injury or death of third-party persons, loss or damage to cargo, claims arising from collisions with other vessels and other damage to other third-party property, including pollution arising from oil or other substances. This insurance is unlimited, except for pollution, which is limited to $1 billion per vessel per incident. The protection and indemnity insurance is maintained through a protection and indemnity association, and as a member of the association, the Partnership may be required to pay amounts above budgeted premiums if the member claims exceed association reserves, subject to certain reinsured amounts. If the Partnership experiences multiple claims each with individual deductibles, losses due to risks that are not insured or claims for insured risks that are not paid, it could have a material adverse effect on the Partnership’s results of operations and financial condition.

18

Table of Contents

As of September 30, 2015, 67.3% of the Partnership’s total number of units outstanding representing limited partner interests were held by the public (in the form of 18,807,500 common units, representing 100% of the Partnership’s common units) and 30.7% of such units were held by KNOT (in the form of 8,567,500 subordinated units, representing 100% of the Partnership’s subordinated units). In addition, KNOT, through its ownership of the General Partner, held the 2% general partner interest (in the form of 558,674 general partner units).

Earnings per unit are determined by dividing net income by the weighted-average number of units outstanding during the applicable period. The General Partner’s, common unitholders’ and subordinated unitholders’ interest in net income are calculated as if all net income was distributed according to the terms of the Partnership Agreement, regardless of whether those earnings would or could be distributed. The Partnership Agreement does not provide for the distribution of net income. Rather, it provides for the distribution of available cash, which is a contractually defined term that generally means all cash on hand at the end of each quarter less the amount of cash reserves established by the Partnership’s board of directors to provide for the proper conduct of the Partnership’s business, including reserves for maintenance and replacement capital expenditures and anticipated capital requirements. In addition, KNOT, as the initial holder of all IDRs, has the right, at the time when there are no subordinated units outstanding and it has received incentive distributions at the highest level to which it is entitled (48.0% for each of the prior four consecutive fiscal quarters), to reset the initial cash target distribution levels at higher levels based on the distribution at the time of the exercise of the reset election. Unlike available cash, net income is affected by non-cash items, such as depreciation and amortization, unrealized gains and losses on derivative instruments and unrealized foreign currency gains and losses.

Under the Partnership Agreement, during the subordination period, the common units will have the right to receive distributions of available cash from operating surplus in an amount equal to the minimum quarterly distribution of $0.375 per unit per quarter, plus arrearages in the payment of the minimum quarterly distribution on the common units from prior quarters, before any distributions of available cash from operating surplus may be made on the subordinated units.

Distributions of available cash from operating surplus will be made in the following manner for any quarter during the subordination period:

In addition, KNOT currently holds all of the IDRs in the Partnership. IDRs represent the rights to receive an increasing percentage of quarterly distributions of available cash from operating surplus after the minimum quarterly distribution and the target distribution levels have been achieved.

If for any quarter:

19

Table of Contents

then, the Partnership will distribute any additional available cash from operating surplus for that quarter among the unitholders and the General Partner in the following manner:

In each case, the amount of the target distribution set forth above is exclusive of any distributions to common unitholders to eliminate any cumulative arrearages in payment of the minimum quarterly distribution. The percentage interests set forth above assume that the General Partner maintains its 2.0% general partner interest and that the Partnership does not issue additional classes of equity securities.

12) Business Acquisitions

In June 2015, December 2015 and June 2014, the Partnership acquired from KNOT equity interests in certain subsidiaries which own and operate the Dan Sabia , the Dan Cisne and the Hilda Knutsen and Torill Knutsen .

The Board and the Conflicts Committee approved the purchase price for each transaction. The Conflicts Committee retained a financial advisor to assist with its evaluation of the transactions. The details of each transaction are as follows:

20

Table of Contents

Dan Sabia

On June 15, 2015, the Partnership’s wholly owned subsidiary, KNOT Shuttle Tankers AS, acquired KNOT’s 100% interest in KNOT Shuttle Tankers 21 AS, the company that owns and operates the Dan Sabia . The purchase price was $103.0 million less assumed bank debt of $64.5 million and other purchase price adjustments of $2.7 million. The cash portion of the purchase price was financed with the proceeds from the Partnership’s public offering of 5,000,000 common units which closed June 2, 2015. See Note 13 – Equity Offerings. The Partnership accounted for this acquisition as an acquisition of a business. The purchase price of the acquisition has been allocated to the identifiable assets acquired. The allocation of the purchase price to acquired identifiable assets was based on their fair values at the date of acquisition.

Revenue and profit contributions

The Dan Sabia business has contributed revenues of $2.9 million and net income of $1.5 million to the Partnership for the period from June 15, 2015 to September 30, 2015.

Dan Cisne

On December 15, 2014, the Partnership’s wholly owned subsidiary, KNOT Shuttle Tankers AS, acquired KNOT’s 100% interest in KNOT Shuttle Tankers 20 AS, the company that owns and operates the Dan Cisne . The purchase price was $103.0 million, less assumed bank debt of $82.2 million less other purchase price adjustments of $2.6 million. The Partnership accounted for this acquisition as an acquisition of a business.

Hilda Knutsen & Torill Knutsen

On June 30, 2014, the Partnership’s wholly owned subsidiary, KNOT Shuttle Tankers AS, acquired KNOT’s 100% interest in: (i) Knutsen Shuttle Tankers 14 AS, the company that owns and operates the Hilda Knutsen and (ii) Knutsen Shuttle Tankers 15 AS, the company that owns and operates the Torill Knutsen . The purchase price of Knutsen Shuttle Tankers 14 AS was $166.0 million, net of $109.6 million of outstanding indebtedness related to the vessel. The purchase price of the Knutsen Shuttle Tankers 15 AS was $169.0 million, net of $112.1 million of outstanding indebtedness related to the vessel. The cash portion of the purchase prices was financed with proceeds from the Partnership’s public offering of 4,600,000 common units which closed on June 27, 2014. See Note 13—Equity Offerings. The purchase prices were subsequently adjusted by a working capital adjustment of $1.0 million. The Partnership accounted for these acquisitions as the acquisitions of businesses.

The table below shows comparative summarized consolidated pro forma financial information for the Partnership for the nine months ended September 30, 2015 and 2014, giving effect to the Partnership’s acquisition and financing of the Dan Sabia , the Dan Cisne , the Hilda Knutsen and the Torill Knutsen as if these acquisitions had taken place on January 1, 2014.

Included in the pro forma adjustments are depreciation related to the purchase price allocation performed on the acquired identifiable assets as if the acquisitions had taken place on January 1, 2014. In addition, the pro forma adjustments include finance expenses related to the increased borrowings as if the acquisitions had taken place on January 1, 2014.

21

Table of Contents

On June 2, 2015, the Partnership sold 5,000,000 common units, representing limited partner interests, in an underwritten public offering (the “June 2015 Offering”). In connection with the June 2015 Offering, the General Partner contributed a total of $2.4 million in order to maintain its 2% general partner interest in the Partnership. The Partnership’s total net proceeds from the June 2015 Offering and the related General Partner’s contribution were $116.6 million.

The Partnership used the net proceeds from the June 2015 Offering to fund the cash portion of the purchase price of the Dan Sabia and to repay the Revolving Credit Facility, the $12.0 million Seller’s Credit and $7.5 million of the Dan Sabia Facility. The remainder of the net proceeds will be available for general partnership purposes.

On June 27, 2014, the Partnership sold 4,600,000 common units, representing limited partner interests, in an underwritten public offering and granted the underwriters a 30-day option to purchase an additional 690,000 common units (the “June 2014 Offering”). In connection with the June 2014 Offering, the Partnership’s general partner contributed a total of $2.7 million in order to maintain its 2% general partner interest in the Partnership. The Partnership’s total net proceeds from the public offering and the related General Partner’s contribution were $128.8 million as of June 30, 2014. In connection with the partial exercise by the underwriters of their option to purchase additional common units, on July 14, 2014 and July 24, 2014, the Partnership issued and sold 150,000 common units and 490,000 common units, respectively, and the General Partner made an additional $0.4 million aggregate capital contribution to the Partnership in order to maintain its 2% general partner interest in the Partnership.

The Partnership used the net proceeds from the June 2014 Offering and related capital contribution by the general partner to fund the cash portion of the purchase prices of the Hilda Knutsen and the Torill Knutsen and for general partnership purposes.

The following table shows the movement in the number of common units, subordinated units and general partner units from the time of the IPO until September 30, 2015.

On August 12, 2015, the Partnership’s board of directors authorized a program for the Partnership to repurchase up to 666,667 of its common units. The board of directors of KNOT Offshore Partners GP LLC (the “General Partner”) concurrently authorized the General Partner to purchase up to 333,333 common units of the Partnership.

22

Table of Contents

All purchases of common units will be at prevailing prices on the open market or in privately negotiated transactions, as permitted by securities laws and other legal requirements. All purchases will be made pursuant to a single program and will be allocated two-thirds to the Partnership and one-third to the General Partner. The program will conclude by August 31, 2016. There is no obligation to purchase any specific number of common units and the program may be modified, suspended, extended or terminated be at any time. Any common units repurchased by the Partnership under the program will be cancelled. Purchases of common units will only take place during periods where the Partnership and the General Partner are not aware of material inside information that would likely affect a seller’s decision to sell.

As of September 30, 2015, no common units have been purchased under the program.

14) Subsequent Events

The Partnership has evaluated subsequent events from the balance sheet date through December 2, 2015, the date at which the unaudited condensed consolidated and combined carve-out financial statements were available to be issued, and determined that there are no other items to disclose, except as follows:

On October 13, 2015, the Windsor Knutsen commenced a two-year time charter with BG Group.

On October 15, 2015 the Partnership’s wholly owned subsidiary, KNOT Shuttle Tankers AS, acquired Knutsen NYK Shuttle Tankers 16 AS (“KNOT 16”), the company that owns the shuttle tanker Ingrid Knutsen , from KNOT for a purchase price of $115.0 million less $104.5 million of outstanding indebtedness related to the vessel, subject to certain post-closing adjustments. The Partnership financed the cash portion of the purchase price with cash on hand.

On the closing of the acquisition, KNOT 16 prepaid $27.0 million of indebtedness related to the vessel, leaving an aggregate of $77.5 million of secured debt, composed of two tranches. Tranche one is a commercial bank loan of $22.4 million, repayable in semi-annual installments with a final balloon payment due at maturity in December 2018. Tranche one bears interest at LIBOR, plus a margin of 2.25%. Tranche two is an export credit loan of $55.1 million, repayable in semi-annual installments with a final balloon payment due at maturity in November 2025. Tranche two bears interest at an annual rate of 3.85%, composed of a 2.5% bank facility rate plus a commission of 1.35% to the export credit guarantor.

The Ingrid Knutsen was delivered in December 2013 and is operating in the North Sea under a ten-year time charter with Standard Marine Tønsberg AS (a Norwegian subsidiary of ExxonMobil), which will expire in the first quarter of 2024. The charterer has options to extend the charter for one three-year period and one two-year period.

The Partnership will account for the acquisition of the Ingrid Knutsen as an acquisition of a business. The purchase price of the acquisition has been allocated to the identifiable assets acquired. The Partnership is in the process of finalizing the accounting for the acquisition and amounts shown below are provisional. Additional business combination disclosures will be presented in the Partnership’s next available interim report. The allocation of the purchase price to acquired identifiable assets was based on their estimated fair values at the date of acquisition. The provisional fair values allocated to each class of identifiable assets of Knutsen NYK Shuttle Tankers 16 AS and the difference between the purchase price and net assets acquired was calculated as follows:

23

Table of Contents

On November 10, 2015, the Partnership announced that Statoil ASA has exercised its option to extend the time charter of the vessel Bodil Knutsen by one additional year until May 2017, with the same hire rate, including a yearly escalation of 1%. Following the declaration of the extension, Statoil ASA has two remaining one-year options to extend the time charter until May 2019.

On November 13, 2015, the Partnership paid a quarterly cash distribution of $0.52 per unit with respect to the quarter ended September 30, 2015. The aggregate amount of the paid distribution was $15.1 million.

As of December 2, 2015, the Partnership and the General Partner had purchased 6,187 and 3,093) common units, respectively, at an average purchase price of $13.985 per unit pursuant to the common unit purchase program.

24

Table of Contents

MANAGEMENT’S DISCUSSION AND ANALYSIS OF

FINANCIAL CONDITION AND RESULTS OF OPERATIONS

Unless the context otherwise requires, references in this report to the “Predecessor,” the “Partnership,” “we,” “our,” “us” or like terms, when used in a historical context (periods prior to April 15, 2013), refer to our predecessor for accounting purposes. References when used in the present tense or prospectively (after April 15, 2013), refer to KNOT Offshore Partners LP and its subsidiaries, also referred to as the “Partnership” or “we.” Those statements in this section that are not historical in nature should be deemed forward-looking statements that are inherently uncertain. See “Forward-Looking Statements” on page 38 for a discussion of the factors that could cause actual results to differ materially from those projected in these statements.

This section should be read in conjunction with our unaudited condensed consolidated and combined carve-out financial statements for the interim periods presented elsewhere in this report, as well as our historical consolidated and combined carve-out financial statements and notes thereto included in our Annual Report on Form 20-F for the year ended December 31,2014 (the “2014 20-F”). Under our Partnership Agreement, KNOT Offshore Partners GP LLC, the general partner of the Partnership (the “General Partner”), has irrevocably delegated to the Partnership’s board of directors the power to oversee and direct the operations of, and to manage and determine the strategies and policies of, the Partnership. During the period from the Partnership’s initial public offering (“IPO”) in April 2013 until the time of the Partnership’s first annual general meeting (“AGM”) on June 25, 2013, the General Partner retained the sole power to appoint, remove and replace all members of the Partnership’s board of directors. From the first AGM, four of the seven board members became electable by the common unitholders and accordingly, from this date, the General Partner no longer retains the power to control the Partnership’s board of directors and, hence, the Partnership. As a result, the Partnership is no longer considered to be under common control with Knutsen NYK Offshore Tankers AS (“KNOT”) and as a consequence, the Partnership will not account for any vessel acquisitions from KNOT as transfer of a business between entities under common control.

On June 15, 2015, the Partnership completed the acquisition of the ownership interests in the company that owns and operates the shuttle tanker Dan Sabia from Knutsen NYK Offshore Tankers AS (“KNOT”). Accordingly, the results of the Dan Sabia are included the Partnership’s results from the date of its acquisition. There has been no retroactive restatement of the Partnership’s financial statements to reflect the historical results of the Dan Sabia prior to its acquisition.

General

We are a limited partnership formed to own, operate and acquire offshore shuttle tankers under long-term charters, which we define as charters of five years or more. Our fleet of shuttle tankers has been contributed to us by KNOT or purchased by us from KNOT. KNOT is jointly owned by TS Shipping Invest AS (“TSSI”) and Nippon Yusen Kaisha (“NYK”). TSSI is controlled by our Chairman and is a private Norwegian company with ownership interests in shuttle tankers, LNG tankers and product/chemical tankers. NYK is a Japanese public company with a fleet of approximately 800 vessels, including bulk carriers, containerships, tankers and specialized vessels.

As of September 30, 2015, we have a modern fleet of nine shuttle tankers that operate under long-term charters with major oil and gas companies engaged in offshore production. We intend to operate our vessels under long-term charters with stable cash flows and to grow our position in the shuttle tanker market through acquisitions from KNOT and third parties. Pursuant to the Omnibus Agreement we have entered into with KNOT in connection with the IPO (the “Omnibus Agreement”); we have the right to purchase from KNOT any shuttle tankers operating under charters of five or more years. This right will continue throughout the entire term of the Omnibus Agreement.

25

Table of Contents

Recent Developments

Ingrid Knutsen Acquisition

On October 15, 2015 the Partnership’s wholly owned subsidiary, KNOT Shuttle Tankers AS, acquired Knutsen NYK Shuttle Tankers 16 AS (“KNOT 16”), the company that owns the shuttle tanker Ingrid Knutsen , from KNOT for a purchase price of $115.0 million less $104.5 million of outstanding indebtedness related to the vessel, subject to certain post-closing adjustments. The Partnership financed the cash portion of the purchase price with cash on hand.

On the closing of the acquisition, KNOT 16 prepaid $27.0 million of indebtedness related to the vessel, leaving an aggregate of $77.5 million of secured debt, composed of two tranches. Tranche one is a commercial bank loan of $22.4 million, repayable in semi-annual installments with a final balloon payment due at maturity in December 2018. Tranche one bears interest at LIBOR, plus a margin of 2.25%. Tranche two is an export credit loan of $55.1 million, repayable in semi-annual installments with a final balloon payment due at maturity in November 2025. Tranche two bears interest at an annual rate of 3.85%, composed of a 2.5% bank facility rate plus a commission of 1.35% to the export credit guarantor.

The Ingrid Knutsen was delivered in December 2013 and is operating in the North Sea under a ten-year time charter with Standard Marine Tønsberg AS (a Norwegian subsidiary of ExxonMobil), which will expire in the first quarter of 2024. The charterer has options to extend the charter for one three-year period and one two-year period.

Carmen Knutsen Charter Amendment

In September 2015, the Partnership entered into amended time charter with Repsol for the Carmen Knutsen , extending the duration of the time charter for five years, while maintaining Repsol’s three one-year extension options. The amended time charter is effective from October 1, 2015, until February 2023, during which period the average charter rate will be reduced by 6.2%.

Bodil Knutsen Charter Extension

In November 2015, Statoil ASA exercised its option to extend the time charter of the vessel Bodil Knutsen by one additional year until May 2017, with the same hire rate, including a yearly escalation of 1%. Following the declaration of the extension, Statoil ASA has two remaining one-year options to extend the time charter until May 2019.

Cash Distributions

On August 14, 2015, we paid a quarterly cash distribution of $0.51 per unit with respect to the quarter ended June 30, 2015. This cash distribution amounted to $14.7 million.

On November 13, 2015, we paid a quarterly cash distribution of $0.52 per unit with respect to the quarter ended September 30, 2015. This cash distribution amounted to $15.1 million.

Annual Meeting

On August 12, 2015, we held our 2015 annual meeting of limited partners at which Andrew Beveridge was re-elected as a Class II director of the Partnership, whose term will expire at the 2019 annual meeting of limited partners.

Common Unit Purchase Program

On August 12, 2015, the Partnership’s board of directors authorized a program for the Partnership to repurchase up to 666,667 of its common units. The board of directors of the General Partner concurrently authorized the General Partner to purchase up to 333,333 common units of the Partnership. As of September 30, 2015, no common units had been purchased under the program. As of December 2, 2015, the Partnership and the General Partner had purchased 6,187 and 3,093 common units, respectively, at an average purchase price of $13.985 per unit.

26

Table of Contents

Time Charter and Bareboat Revenues: Time charter and bareboat revenues increased by $5.0 million to $39.3 million for the three months ended September 30, 2015 compared to $34.3 million for the three months ended September 30, 2014. This was mainly due to increased time charter earnings from the Dan Sabia being included in our results of operations from June 15, 2015 and the Dan Cisne being included in our results of operations from December 15, 2014.

Other income: Other income for the three months ended September 30, 2015 was $3,000 compared to $18,000 for the three months ended September 30, 2014.

Vessel operating expenses: Vessel operating expenses for the three months ended September 30, 2015 were $5.9 million, a decrease of $1.7 million from $7.6 million in the three months ended September 30, 2014. The decrease was primarily due to receipt of insurance proceeds of $0.7 million and generally lower operating expenses mainly due to strengthening of the dollar against Norwegian Kroner.

Depreciation: Depreciation expense for the three months ended September 30, 2015 was $12.4 million, an increase of $2.2 million from $10.2 million in the three months ended September 30, 2014. This increase was mainly due to the Dan Cisne being included in our results of operations from December 15, 2014, and the Dan Sabia being included in our results of operations from June 15, 2015.

General and administrative expenses: General and administrative expenses for the three months ended September 30, 2015 were $1.2 million, an increase of $0.2 million from $1.0 million in the three months ended September 30, 2014. The increase was mainly due to incremental expenses during the three months ended September 30, 2015 in connection with the preparation for the acquisition of the Ingrid Knutsen .

Interest expense: Interest expense for the three months ended September 30, 2015 was $4.3 million, an increase of $0.3 million from $4.0 million for the three months ended September 30, 2014. This is principally due to increased interest expense of $0.8 million due to increased indebtedness related to the acquisitions of the Dan Cisne and Dan Sabia Knutsen which was partially offset by lower interest expenses due to lower principal on remaining vessels for the three months ended September 30, 2015 compared to the same period last year.

Other finance expense: Other finance expense was $79,000 for the three months ended September 30, 2015 and $96,000 the three months ended September 30, 2014.

Realized and unrealized gain (loss) on derivative instruments: Realized and unrealized gain (loss) on derivative instruments for the three months ended September 30, 2015 was a loss of $6.5 million, compared to a gain of $1.1 million for the three months ended September 30, 2014, as set forth in the table below

27

Table of Contents

As of September 30, 2015, the total notional amount of the Partnership’s outstanding interest rate swap contracts that were entered into in order to hedge outstanding or forecasted debt obligations was $412.3 million. The increased unrealized loss on interest rate swap contracts was due to an increase in the notional amount of the Partnership’s swap contracts as well as a decrease in long-term swaps rate during the three months ended September 30, 2015 compared to the three months ended September 30, 2014. As of September 30, 2015, we had entered into foreign exchange forward contracts, selling total notional amount of $25.0 million against NOK at an average exchange rate of NOK 7.79 per 1.0 U.S. Dollar, which are economic hedges for certain vessel operating expenses and general expenses in NOK. During the three months ended September 30, 2015, the Partnership executed two foreign exchange forward contracts which resulted in a realized a loss of $3.2 million and the Partnership entered into new foreign exchange forward contracts which resulted in unrealized gain of $1.8 million.

Net gain (loss) on foreign currency transactions: Net gain (loss) on foreign currency transactions for the three months ended September 30, 2015 was a net loss of $75,000 compared with a net gain of $68,000 for the three months ended September 30, 2014.

Income tax benefit (expense): Income tax expense for the three months ended September 30, 2015 was $nil and for the three months ended September 30, 2014 was $1,000.

Net income: As a result of the foregoing, we earned net income of $8.8 million for the three months ended September 30, 2015 compared to net income of $12.6 million for the three months ended September 30, 2014.

Time Charter and Bareboat Revenues: Time charter and bareboat revenues increased by $34.2 million to $112.3 million for the nine months ended September 30, 2015 compared to $78.1 million for the nine months ended September 30, 2014. This was principally due to increased time charter earnings resulting from the Hilda Knutsen and Torill Knutsen being included in our results of operations from July 1, 2014, the Dan Cisne being included in our results of operations from December 15, 2014, and Dan Sabia being included in our results of operations from June 15, 2015.

Other income: Other income for the nine months ended September 30, 2015 was $154,000 compared to $29,000 for the nine months ended September 30, 2014.

Vessel operating expenses: Vessel operating expenses for the nine months ended September 30, 2015 were $19.9 million, an increase of $3.4 million from $16.5 million in the nine months ended September 30, 2014. This was principally due to increased time charter earnings resulting from the Hilda Knutsen and Torill Knutsen being included in our results of operations from July 1, 2014, partially offset by lower operating expenses for the nine months ended September 30, 2015 compared to the nine months ended September 30, 2014 mainly due to strengthening of the dollar against Norwegian Kroner.

Depreciation: Depreciation expense for the nine months ended September 30 2015 was $35.4 million, an increase of $11.6 million from $23.8 million in the nine months ended September 30, 2014. The increase was mainly due to the Hilda Knutsen and Torill Knutsen being included in our results of operations from July 1, 2014, the Dan Cisne being included in our results of operations from December 15, 2014, and Dan Sabia being included in our results of operations from June 15, 2015.

28

Table of Contents

General and administrative expenses: General and administrative expenses for the nine months ended September 30, 2015 were $3.2 million, a decrease of $0.3 million from $3.5 million for the nine months ended September 30, 2014. The decrease was mainly due to incremental expenses during the nine months ended September 30, 2014 in connection with the preparation for the acquisitions of Hilda Knutsen and Torill Knutsen and our June 2014 common unit offering.

Goodwill impairment charge: Goodwill impairment charge for the nine months ended September 30, 2015 was $6.2 million and $nil for the nine months ended September 30, 2014. During the three months ended June 30, 2015, the Partnership concluded that there were indicators of impairment due to a significant reduction in the price of the Partnership’s common units during the quarter. Consequently, the Partnership performed an interim vessel and goodwill impairment analysis as of June 30, 2015 on its fleet, concluding that there was no impairment to the vessels’ values. However, the Partnership determined that the carrying value of the goodwill exceeded its fair value. The impairment charge relates mainly to capitalized goodwill which arose in 2008 when the Partnership’s predecessor acquired the Windsor Knutsen and three other vessels then under construction, in a transaction that was then accounted for as a step transaction. As a result, a goodwill impairment charge of $6.2 million was recognized in the condensed consolidated and combined carve-out financial statements for the nine months ended September 30, 2015. The fair value was determined using the present value of the expected future cash flows discounted at a rate equivalent to a market participant’s weighed average cost of capital. The estimates and assumptions regarding expected future cash flows and appropriate discount rates are in part based upon existing contracts, future shuttle tanker rates, historical experience, financial forecasts and industry trends and conditions.

Interest income: Interest income for the nine months ended September 30, 2015 was $3,000 compared to $4,000 for the nine months ended September 30, 2014.

Interest expense: Interest expense for the nine months ended September 30, 2015 was $12.7 million, an increase of $2.1 million from $10.6 million in the nine months ended September 30, 2014. The increase is primarily due to the increased indebtedness related to the acquisitions of the Hilda Knutsen and Torill Knutsen on June 30, 2014, Dan Cisne on December 15, 2014, and Dan Sabia on June 15, 2015. The increase is partially offset by a one-time charge relating to reversal of capitalized loan costs of $1.1 million for the nine months ended September 30, 2014 and a lower margin in 2015 due to refinancing in 2014.

Other finance expense: Other finance expense for the nine months ended September 30, 2015 was $0.2 million, a decrease of $1.0 million from $1.2 million for the nine months ended September 30, 2014. Other finance expenses are primarily related to bank fees and guarantee commissions. Other finance expense of $1.2 million for the nine months ended September 30, 2014 was mainly due to (i) $0.4 million payment as compensation to banks for lost loan margin on repaid loans, (ii) $0.4 million guarantee commission of the outstanding amount under the Guarantee Institute for Export Credits guarantee related to the $120 million Bodil Knutsen credit facility, which was repaid in full in June 2014 and (iii) $0.3 million in other finance expenses.

Realized and unrealized gain (loss) on derivative instruments: Realized and unrealized loss on derivative instruments for the nine months ended September 30, 2015 was $11.8 million, compared to a loss of $1.2 million for the nine months ended September 30, 2015 in 2014, as set forth in the table below: