SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

Date: May 8, 2019

Item 1

Banco Santander México, S.A. and Subsidiaries

The consolidated financial statements of Banco Santander México, S.A., Institución de Banca Múltiple, Grupo Financiero Santander México (together with its subsidiaries, the “Bank”) filed for Mexican statutory purposes are prepared in accordance with accounting principles and regulations prescribed by the Mexican Banking and Securities Commission ( Comisión Nacional Bancaria y de Valores , or “CNBV”), as amended, which are hereinafter referred to as Mexican Banking GAAP. Mexican Banking GAAP is composed of Mexican Financial Reporting Standards ( “NIF” by its Spanish acronym), as issued by the Mexican Board of Financial Reporting Standards (“CINIF”), which, in turn, are supplemented and modified by specific rules mandated by the CNBV. The CNBV’s accounting rules principally relate to the recognition and measurement of impairment of loans and receivables, sale and repurchase agreements, securities loans, consolidation of special purpose entities and foreclosed assets.

The most significant differences between Mexican Banking GAAP and International Financial Reporting Standards (“IFRS”), as they relate to the Bank, are reconciled and described below:

Reconciliation of net income for the quarter ended March 31, 2019

Amounts in millions of Mexican pesos, net of Income Tax effect

Reconciliation of Total equity as of March 31, 2019

Amounts in millions of Mexican pesos, net of Income Tax effect

Reconciliation of Cash and cash equivalents as of March 31, 2019

Amounts in millions of Mexican pesos

A description of the IFRS adjustments is presented below:

Mexican Banking GAAP requires the recognition of the deferred compulsory employee profit sharing effect based on the temporary differences arising between book and tax value of the assets and liabilities, while IFRS does not considers this deferred employee profit sharing as an income tax temporary difference.

Adjustments were made to recognize the effects of the first-time IFRS adoption exemption taken in which all unrecognized actuarial gains and losses related to pension and post-employment benefits were recognized on January 1, 2010. For Mexican Banking GAAP purposes, the net pension liability represents the present value of the defined benefit obligation, plus (minus) the unrecognized actuarial

gains or losses of the pension plan, while IFRS requires that the net pension liability reflects the full value of the underfunded status of the pension plan.

IFRS requires the immediate recognition of actuarial gains and losses of the year in other comprehensive income without subsequent recycling to profit or loss. Under Mexican Banking GAAP, there is an option to recognize actuarial gains and losses from the year:

For IFRS purposes, the Bank assesses on a forward-looking basis the expected credit losses associated with its financial assets carried at amortized cost and at fair value through other comprehensive income. The impairment methodology applied depends on whether there has been a significant increase in credit risk; once the Bank has classified its financial assets according to its credit risk, they are individually or collectively assessed for impairment in order to recognize the allowance for impairment losses arising from credit risk. The expected credit losses model is based on changes in credit quality since initial recognition and considers the following stages:

Such IFRS criteria differ from the related criteria for Mexican Banking GAAP under which impairment losses and provisions for off-balance sheet risk are determined using prescribed formulas that are based primarily on an expected credit losses model. The expected credit losses model formulas are developed by the CNBV using credit losses information compiled from the Mexican lending market as a whole, which may differ significantly from the Bank’s credit loss experience. In some cases, CNBV can approve the use of internal models to determine the allowance for impairment losses under Mexican Banking GAAP, as an alternative to the regulatory expected credit losses model.

Under Mexican Banking GAAP, impairment losses from non-current assets held for sale are determined based on formulas prescribed by the CNBV. For IFRS purposes, the Bank determines an estimation based upon the comparison between the fair value less costs to sell and the carrying value of the non-current asset.

For Mexican Banking GAAP, the fair value measurement of over-the-counter ( “OTC”) derivatives does not consider the counterparty credit risk or the Bank’s own credit risk. For IFRS purposes, the counterparty credit risk and the Bank’s own credit risk is factored into the fair value measurements of OTC derivatives.

Due to the lack of trading volume for certain financial instruments, the quoted market prices of such instruments may not have deemed to be sufficiently current for purposes of measuring fair value under IFRS. The adjustments were applicable to 28-day Interbank Equilibrium Interest Rate ( Tasa de Interés Interbancaria de Equilibrio , or “TIIE”) future contracts traded in the Mexican Derivatives Exchange (“MexDer”). The Mexican Banking GAAP fair values of these financial instruments are the unadjusted quoted market prices (MexDer prices).

This adjustment also includes the reversal of a reserve for the probable future decrease in value of Special CETES that was created by the Bank permitted by the CNBV for Mexican Banking GAAP purposes. The Reserve for Special CETES does not meet the recognition criteria under IFRS.

For Mexican Banking GAAP, the balance of the loan portfolio indexed to the minimum salary is adjusted by the current minimum salary rate recognizing an increase in its balance and a deferred credit balance, which will be recognized in profit or loss in a twelve-month period as interest income. Under IFRS, the aforementioned effect is recognized immediately in profit or loss of the period as a gain on financial assets.

For Mexican Banking GAAP, “Cash and cash equivalents” or “Funds available” include some items that are mandatory to be presented in this line of the balance sheet but do not comply with the definition of “Cash and cash equivalents” under IFRS.

Item 2

Banco Santander México, S. A., Institución de Banca Múltiple
Grupo Financiero Santander México and Subsidiaries
Unaudited Condensed Consolidated Interim Financial Statements
as of March 31, 2019 and as of December 31, 2018 and
for the quarters ended March 31, 2019 and 2018

In millions of Mexican pesos

The accompanying notes are an integral part of these unaudited condensed consolidated interim financial statements.

The accompanying notes are an integral part of these unaudited condensed consolidated interim financial statements.

Banco Santander México, S. A., Institución de Banca Múltiple
Grupo Financiero Santander México and Subsidiaries
Unaudited Condensed Consolidated Statements of Changes in Stockholders’ Equity

In millions of Mexican pesos

The accompanying notes are an integral part of these unaudited condensed consolidated interim financial statements.

The accompanying notes are an integral part of these unaudited condensed consolidated interim financial statements.

Amounts in millions of Mexican pesos

Note 1 - Activity and economic and regulatory environment

Banco Santander México, S. A., Institución de Banca Múltiple, Grupo Financiero Santander México (the “Bank”) is a subsidiary of Grupo Financiero Santander México, S.A. de C.V. (the “Financial Group”), which holds 99.99% of its common stock, which is a subsidiary of Banco Santander, S.A. in Spain (Banco Santander (Spain)). The Bank and its subsidiaries (the “Institution”) is regulated by, among others, the Credit Institutions Law and the General Provisions issued by the Mexican National Banking and Securities Commission (the “Commission”) and Banco de México (the “Central Bank”). The Institution’s corporate purpose is to render banking and credit services under the terms of applicable laws, which services include, among others, reception of deposits, acceptance of loans, granting of loans, trading of securities and the execution of trust contracts.

During the quarter period ended March 31, 2019, the macroeconomic indicators have been stable, with inflation of 0.44%, estimated GDP annual growth of 1.7% and appreciation of the Mexican peso with respect to the U.S. dollar of 1.4%.

Events after the reporting period

On April 8, 2019, the Bank issued debt securities denominated unsecured notes with the following characteristics: i) $2,300 with a 1,092-day maturity that will bear interest at an interest rate of 28 day Interbank Equilibrium Interest Rate (Tasa de Interés Interbancaria de Equilibrio, or TIIE) plus 0.10 % (interest will be paid every 28 days) and ii) $4,600 with a 2,548-day maturity that will bear interest at an interest rate of 8.95% (interest will be paid every 182 days).

Banco Santander (Spain) announced its intention of making a public acquisition offer to acquire up to approximately 25% of the shares of the Bank, which are owned by investors other than Banco Santander (Spain). The investors which accept the offering will obtain 0.337 of shares of Banco Santander (Spain) for each share of the Bank and 1,685 American Depositary Shares (ADS) of Banco Santander (Spain) for each ADS of the Bank. It is expected to make the offering and settle the exchange of shares during the second half-year of 2019.

No additional significant events occurred from April 1, 2019 to the date on which these unaudited condensed consolidated interim financial statements were authorized for issue.

Note 2 - Basis of presentation of the unaudited condensed consolidated interim financial statements

These unaudited condensed consolidated interim financial statements were prepared and are presented in accordance with the Accounting Criteria established by the Commission, which incorporate on a supplemental basis, the accounting and reporting requirements set forth in the Mexican Financial Reporting Standard (“MFRS” or “NIF” by its Spanish acronym), B-9, Interim Financial Information (“NIF B-9”) as issued by the Mexican Board of Financial Reporting Standards (“CINIF”). The results of the quarters are not necessarily indicative of the results for the full year. These unaudited condensed consolidated interim financial statements should be read in conjunction with the audited financial statements of the Institution and the respective notes for the year ended December 31, 2018 as issued on March 14, 2019.

The issuance of these unaudited condensed consolidated interim financial statements was authorized by Héctor Blas Grisi Checa, Executive President and Chief Executive Officer (CEO) and Director and by the Board of Directors Bank on April 25, 2019. These unaudited condensed consolidated interim financial statements are pending the

approval of the ordinary shareholders’ meeting, where they may be modified, based on provisions set forth in the Mexican Corporations Law (Ley General de Sociedades Mercantiles).

Note 3 - Explanation for translation into English

The accompanying unaudited condensed consolidated interim financial statements have been translated from Spanish into English for use outside of México. Certain accounting practices applied by the Institution may not conform to accounting principles generally accepted in the country of use.

Note 4 - Significant accounting policies

The same accounting policies, presentation and methods of computation have been followed in these unaudited condensed consolidated interim financial statements as were applied in the preparation of the Institution’s financial statements for the year ended December 31, 2018.

These unaudited condensed consolidated interim financial statements and notes as of March 31, 2019 and 2018 and for the year ended December 31, 2018, include balances and transactions in Mexican pesos of different purchasing power.

The accompanying unaudited condensed consolidated interim financial statements include those of the Bank and its subsidiaries mentioned below. All balances and transactions among the Bank and its subsidiaries have been eliminated.

Below is a breakdown of the consolidated subsidiaries and the Bank’s equity percentage as of March 31, 2019:

During the quarter ended as of March 31, 2019, no changes have occurred in the method and in the scope of consolidation.

Basic earnings per share are calculated by dividing the net income attributable to controlling interest by the weighted average number of shares outstanding during the year, excluding the average number of treasury shares, if any, held in the year.

Accordingly, basic earnings per share for the quarter ended March 31, 2019 and 2018 were determined as follows:

In calculating diluted earnings per share, the amount of net income before non-controlling interest and the weighted average number of shares issued, excluding the average number of treasury shares, are adjusted to consider all the dilutive effects inherent to potential shares.

Accordingly, diluted earnings per share for the quarter ended March 31, 2019 and 2018 were determined as follows:

Changes in accounting policies applicable in 2019

Changes in Accounting Criteria issued by the Commission

Accounting Criteria B-6, Loan portfolio and Accounting Criteria D-2, Income Statement

On December 27, 2017, certain amendments were published in the Federal Official Gazette (DOF by its Spanish acronym) to the Accounting Criteria issued by the Commission. These Accounting Criteria applicable to credit institutions are adjusted so that they can cancel, in the period in which they occur, the surpluses in the income statement of the allowance for loan losses, as well as to recognize the recovery of credits previously written-off against the heading “Allowance for loan losses” of the income statement in order to be consistent with international accounting standards established in International Financial Reporting Standards (IFRS).

This amendment is mandatory on January 1, 2019.

Changes in the NIF issued by the CINIF

Improvements to NIF 2019

Starting January 1, 2019, the Bank prospectively adopted the following Improvements to the NIF, which were issued by the CINIF and were effective on the aforementioned date. These Improvements to the NIF did not have a significant impact on the financial information presented by the Bank.

NIF C-6, Property, plant and equipment

NIF C-6 establishes that the assets delivered or, if applicable, the assets received in an exchange of assets must be valued at their fair value. Entity must determine such valuation of fair value according to NIF B-17, Determination of fair value .

NIF C-14, Transfer and derecognition of financial assets

Drafting amendment are made on the transfer of risks and benefits for greater clarity.

NIF D-3, Employee benefits

A transfer of personnel between entities with recognition of seniority implies for the entity that receives the staff the recognition of a retroactive effect of a Modification to the Plan for the introduction of a new plan. For the entity that transfers implies an Early Settlement of Obligations. In the consolidated financial statements, the effects of the transfers between entities of the group are eliminated, unless the benefits are changed at the time of the transfer.

A transfer of personnel between entities under common control with recognition of seniority involves recognizing in the stand alone financial statements of the entity that receives the staff a retroactive effect of a Modification to the Plan equivalent to an introduction of a new plan and for the entity that transfer implies an Early Settlement of Obligations. In the consolidated financial statements, the transfer of personnel has no effect, unless the benefits are changed at the time of the transfer.

The interest rate used to discount post-employment benefit obligations (funded or not funded) must be an interest rate without or with very low credit risk, such as the interest rate of government bonds and the interest rate of high quality corporate bonds in absolute terms in a deep market, respectively. The chosen interest rate should be used consistently over time. The currency and term of the bonds utilized to obtain the discount rate must be consistent with the currency and the estimated term for the payment of the Defined Benefit Obligation (DBO). The entity must justify the use of a certain interest rate and, in the case of a change of the discount rate, must justify this fact. Any effect on the present value of the labor liability from a change in the discount rate (from government bonds to corporate bonds or vice versa) should be considered as a change in accounting estimate and recognized prospectively, when this occurs, in the income statement of the period based on the provisions of NIF B-1, Accounting changes and error corrections .

The Labor Cost of Past Services is the increase or decrease in the DBO for services rendered by employees in previous periods, from:

i. Introduction of a new benefit plan,
ii. Benefits assumed by the transfer of employees,
iii. Withdrawal of a benefit plan, or
iv. Subsequent changes in benefits payable in an established benefit plan; and

A Modification to the Plan occurs when an entity introduces a previously non-existent plan, withdraws or changes the benefits of a defined benefit plan and a Personnel Reduction occurs when an entity significantly reduces the obligation for a reduction in the number of employees covered by the plan (it may arise from an isolated event, such as the closure of a plant or the discontinuance of an operation); this generates a Labor Cost of Past Services that is equivalent to the difference between the current DBO and the previous DBO, including, in the case of Personnel Reduction, the payments made by the entity, which corresponds to the increase or decrease in the obligation due to the retroactive effect of previous services on the benefits to employees when performing a Modification to the Plan or Personnel Reduction.

Note 5 - Investment in securities

Trading securities - As of March 31, 2019 and December 31, 2018, trading securities were as follows:

As of March 31, 2019 and December 31, 2018, the investment in CETES, M Bonds, UDIBONDS, BPATS and shares listed in stock exchanges includes the amount of $23,569 and $29,068, respectively, which refers to the collateral provided for securities loan transactions in which the lender is the Central Bank and other institutions, which was classified as restricted under the heading “Trading securities” in the unaudited condensed consolidated balance sheet.

As of March 31, 2019 and December 31, 2018, the related liability of $24,006 and $30,539, respectively, is recorded under the heading of “Collateral sold or pledged as guarantee” in the unaudited condensed consolidated balance sheet which corresponds the obligation to restore the value of collateral as follows:

As of March 31, 2019 and December 31, 2018, trading securities include $50,659 and $74,548 respectively that are under sale and repurchase agreements for which reason they are considered as a restricted position.

Securities available for sale - As of March 31, 2019 and December 31, 2018, securities available for sale are comprised as follows:

As of March 31, 2019 and December 31, 2018 of the government and private securities related to M Bonds, UMS, BPATS, UDIBONDS and unsecured bonds, the amounts of $15,035 and $20,082 respectively, are under sale and repurchase agreements for which reason they are classified as restricted positions.

Securities held to maturity - As of March 31, 2019 and December 31, 2018, securities held to maturity were as follows: