Company: BCDRF
Filing Date: 2025-03-03
Form Type: 6-K
Source: 0000891478-25-000057
Chunk: 0

Company: Banco Santander, S.A.
Filing Date: 2025-03-03
Form: 6-K
Chunk 0
---
#### FORM 6-K

### SECURITIES AND EXCHANGE COMMISSION

#### Washington, D.C. 20549

#### Report of Foreign Issuer

#### Pursuant to Rule 13a-16 or 15d-16

#### of the Securities Exchange Act of 1934

#### For the month of March, 2025

#### Commission File Number: 001-12518

#### Banco Santander, S.A.
<div align='center'>(Exact name of registrant as specified in its charter)</div>

#### Ciudad Grupo Santander

#### 28660 Boadilla del Monte (Madrid) Spain
<div align='center'>(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 ☒ Form 40-F ☐</div>

#### Banco Santander, S.A.
<div align='center'>TABLE OF CONTENTS</div>

| Item |     |                             |
| 1    |     | 2024 Pillar III Disclosures |

a

Profitable growth and value creation

Index

| Introduction(Ch. 1) |     |                                         |
| 6                   |     | Santander overview                      |
| 13                  |     | GrupoSantander Pillar 3 Report overview |
| 16                  |     | Regulatory framework                    |
| 22                  |     | Scope of consolidation                  |

| Capital(Ch. 2) |     |                                                |
| 28             |     | Capital                                        |
| 32             |     | Capital function                               |
| 34             |     | Capital management, adequacy and profitability |
| 39             |     | Regulatory capital- Pillar 1                   |
| 50             |     | Leverage ratio                                 |
| 55             |     | Economic capital - Pillar 2                    |
| 55             |     | Capital planning and stress tests              |
| 56             |     | TLAC & MREL                                    |

| Risks(Ch. 3, 4, 5, 6, 7, 8, 9, 10  and 11) |     |                               |
| 64                                         |     | Global risk vision            |
| 72                                         |     | Credit Risk                   |
| 142                                        |     | Counterparty Credit Risk      |
| 156                                        |     | Credit Risk -