Banco Santander S A : Supplement to the notice of call to the 2023 ordinary general shareholders’ meeting of Banco Santander, S.A. directed to Polish investors

Supplement to the notice of call to the ordinary general

shareholders' meeting of Banco Santander, S.A.

This document constitutes a supplement to the notice of call to the ordinary general shareholders' meeting of Banco Santander, S.A. (the "Company") to be held in Boadilla del Monte, at Centro de Formación el Solaruco (Ciudad Grupo Santander) (Avenida de Cantabria s/n), on 31 March 2023 at 10:00 a.m. (CEST), on second call, in the event that, due to failure to reach the required quorum, such meeting cannot be held on first call, which has been also convened to be held at the same place and time on 30 March 2023 as announced on 28 February 2023 by way of the corresponding public notices. Furthermore, the announcement of the call to meeting has also been published on a Spanish newspaper on 28 February 2023.

The Company is organised and exists under Spanish law. Accordingly, the rights and obligations of the Company's shareholders as well as the holding of and the participation in the general shareholders' meeting are regulated by Spanish corporate law. Under Spanish law, only shareholders that are registered as holders of shares five days prior to the date on which the general shareholders' meeting is to be held may participate in such meetings and exercise their voting rights.

This supplement is directed exclusively to the investors holding shares in the Company through the Polish National Depositary of Securities (Krajowy Depozyt Papierów Wartościowych) (the "NDS") with the intermediation of Euroclear Bank SA/NV ("Euroclear") (the "Polish Investors"). Euroclear's link with the Spanish depositary, Iberclear, operates via the services of a participant in Iberclear, through which Euroclear (through its subsidiary, E.C. Nominees Limited ("Euroclear Nominees")) holds shares in the Iberclear system for the Polish Investors.

Due to the fact that Euroclear Nominees is the registered holder of the shares in the Company for the benefit of the Polish Investors, such investors will only be able to enforce the rights attached to the shares to the extent of, and pursuant to, the terms and conditions of the arrangements among Euroclear, Euroclear Nominees, the NDS and the relevant Polish depository investment firms, and, as a result of certain aspects of Spanish law that govern the shares, will not be able to directly enforce or exercise those rights. However, such rights may be exercised through the NDS and, consequently, Euroclear. Given the above, the exercise by the Polish Investors of their rights to participate in and vote at the general shareholders' meeting will differ from the exercise of such rights by the investors holding the shares in the Company directly via Iberclear system.

The information included in this document that relates to certain procedures specifically applicable to Polish Investors is based exclusively on the information provided to the Company by the NDS.

Polish Investors are encouraged to contact in advance the respective investment firms maintaining their securities accounts (the "NDS participants") in order to obtain detailed information related to the participation in and voting at the general shareholders' meeting, including in particular the ultimate deadline by which each Polish Investor may exercise

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his/her voting rights and the relevant documents or data that need to be provided by such Polish Investor.

1. Participation in and voting at the ordinary general shareholders' meeting of the Polish Investors
   1. General remarks

The Polish Investors may participate in and vote at the ordinary general shareholders' meeting by way of: (i) personal voting by proxy; or (ii) the issuance of voting instructions pursuant to the rules of the Euroclear system, as supplemented by the terms and conditions governing the relationship between the investors and the depository investment firms operating their securities accounts.

The right to exercise the above-mentioned rights at the general shareholders' meeting by the Polish Investors will be established on the basis of the balance of their securities accounts maintained by the respective NDS participants five days prior to the meeting, including all of the transactions that have been settled up to such date (inclusive).

In order to be able to duly exercise the above-mentioned rights at the general shareholders' meeting, the Polish Investors will be provided with the relevant information and documentation by the NDS participants that maintain their securities accounts, and they should contact such NDS participants in case of any queries with regard to their rights.

2. Personal voting by proxy

Personal voting by the Polish Investors at the general shareholders' meeting implies attending the meeting in person and will require Euroclear Nominees, as the registered shareholder of the Company, to issue powers of attorney in favour of the Polish Investors or in favour of the person expressly designated thereby. Such proxy-holder may freely vote by attending the general shareholders' meeting in person. To that end, a Polish Investor should declare to its investment firm the willingness to attend the meeting and vote in person and such information should be transferred by the investment firm to the NDS and consequently to Euroclear. Then, Euroclear Nominees must grant such powers of attorney and deliver them to the Company within the applicable deadline determined by the Company. The data that should be provided by the Polish Investor wishing to attend the meeting and vote in person will be determined by Euroclear and delivered to the Polish Investor by the NDS with the intermediation of the NDS participants.

3. Voting by instructions

The Polish Investors who wish to vote by instruction should give their voting instructions with regard to the general shareholders' meeting to the NDS participants operating the securities accounts in which such investors' shares are registered, and such NDS participants will then deliver the instructions to the NDS. Subsequently, the NDS will deliver the voting instructions to Euroclear, which, through Euroclear Nominees, the registered holder of the shares in the Company, will vote at the general shareholders' meeting pursuant to the instructions received from the Polish Investors. The form of the instructions will be provided to the Polish Investors by their investment firm.

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Voting by instruction will not require the disclosure of the relevant Polish Investor's personal data to the Company.

1. The English translation of the proposed agenda of the ordinary general shareholders' meeting

The text of the agenda of the ordinary general shareholders' meeting included below is a translation of an original text in Spanish. In case of any discrepancy between both texts, the Spanish version will prevail.

1 Annual accounts and corporate management.

1 A Annual accounts and directors' reports of Banco Santander, S.A. and of its consolidated group for 2022.

1 B Consolidated statement of non-financial information for 2022, which is part of the consolidated directors' report.

1 C Corporate management for 2022.

1. Application of results obtained during 2022.
2. Board of directors: appointment, re-election or ratification of directors.
   3 A Setting of the number of directors.
   3 B Ratification of the appointment and re-election of Mr Héctor Blas Grisi Checa. 3 C Ratification of the appointment and re-election of Mr Glenn Hogan Hutchins. 3 D Re-election of Mrs Pamela Ann Walkden.
   3 E Re-election of Ms Ana Patricia Botín-Sanz de Sautuola y O'Shea.
   3 F Re-election of Ms Sol Daurella Comadrán.
   3 G Re-election of Ms Gina Lorenza Díez Barroso Azcárraga.
   3 H Re-election of Ms Homaira Akbari.
3. Re-electionof the external auditor for financial year 2023.
4. Share capital and convertible securities.
   5 A Reduction in share capital in the maximum amount of EUR 757,225,978.50, through the cancellation of a maximum of 1,514,451,957 own shares. Delegation of powers.
   5 B Reduction in share capital in the maximum amount of EUR 822,699,750.50, through the cancellation of a maximum of 1,645,399,501 own shares. Delegation of powers.
   5 C Authorisation for the Bank and its subsidiaries to be able to acquire own shares.
   5 D Delegation to the board of the power to issue securities convertible into shares of the Bank within a 5-year period and subject to a maximum aggregate limit of EUR 10,000 million. Setting of standards to determine the

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bases for and terms and conditions applicable to the conversion and granting of powers to increase capital. Delegation to exclude pre-emptive rights.

1. Remuneration.
   6 A Directors' remuneration policy.
   6 B Setting of the maximum amount of annual remuneration to be paid to all the directors in their capacity as such.
   6 C Approval of maximum ratio between fixed and variable components of total remuneration of executive directors and other employees belonging to categories with professional activities that have a material impact on the risk profile.
   6 D Deferred Multiyear Objectives Variable Remuneration Plan.
   6 E Application of the Group's buy-out regulations.
   6 F Annual directors' remuneration report (consultative vote).
2. Authorisation to the board and grant of powers for conversion into public instrument.

1. Documents available on the Company's website

The following documents and information, among others, are available on the Company's corporate website (www.santander.com) from the date of publication of the announcement of the call to the ordinary general shareholders' meeting and once it has been communicated to the National Securities Market Commission (Comisión Nacional del Mercado de Valores):

1. The announcement of the call to meeting.
2. This supplement.
3. The total number of shares and voting rights on the date of the call to meeting.
4. The full text of the proposed resolutions regarding all of the items on the agenda for the general shareholders' meeting, as well as the corresponding explanatory reports.
5. The curricula vitae of the individuals referred to in item 3 of the agenda, including the category of each director.
6. The rules applicable to proxy-granting and voting by remote means of communication and to remote attendance at the meeting and the documentation necessary for such purpose.
7. 2022 individual annual accounts and directors' report (including the statement of non- financial information) of Banco Santander, S.A. and auditor's report.
8. 2022 annual report, which contains:
9. 1. 2022 consolidated annual accounts (which include the annual banking report) and the Group's auditor's report; and
   2. the consolidated directors' report, which includes, in relation to financial year 2022:

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(b.1) the consolidated statement of non-financial information and the independent services provider's verification report ("Responsible banking" chapter); and

(b.2) the annual report on corporate governance ("Corporate governance" chapter), which includes, among others:

(b.2.1) the report of the audit committee (which also includes the report on the independence of the auditor) (section 4.5);

(b.2.2) the report of the nomination committee (section 4.6);

(b.2.3) the report of the remuneration committee (which also includes the specific report on the director remuneration policy to which item 6 A of the agenda refers) (section 4.7);

(b.2.4) the report of the risk supervision, regulation and compliance committee (section 4.8);

(b.2.5) the report of the responsible banking, sustainability and culture committee (section 4.9);

(b.2.6) the report of the innovation and technology committee (section 4.10);

(b.2.7) the report of the audit committee on related-party transactions (section 4.12);

(b.2.8) the directors' remuneration policy referred to in item 6 A on the agenda (sections 6.4 and 6.5); and

(b.2.9) the annual directors' remuneration report submitted to a consultative vote under item 6 F on the agenda (sections 6 (except for 6.4 and 6.6), 9.4 and 9.5).

1. The Bylaws in force.
2. The Rules and Regulations for the General Shareholders' Meeting in force.
3. The Rules and Regulations of the Board of Directors in force.
4. The rules of operation of the Electronic Shareholders' Forum.
5. The valid requests for information, clarification or questions asked by shareholders exercising their right to receive information and any answers provided by the directors (only if, and when, submitted).

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