Company: BCDRF
Filing Date: 2025-09-04
Form Type: 6-K
Source: 0000950103-25-011255
Chunk: 1

Company: Banco Santander, S.A.
Filing Date: 2025-09-04
Form: 6-K
Chunk 1
---
190,744 |            8.0453 |
| 03/09/2025 | SAN      | Purchase    | XMAD    |   833,728 |            8.0462 |
| 03/09/2025 | SAN      | Purchase    | CEUX    |    84,308 |            8.0558 |
| 03/09/2025 | SAN      | Purchase    | TQEX    |    34,792 |            8.0369 |
| 03/09/2025 | SAN      | Purchase    | AQEU    |    47,172 |            8.0623 |
|            |          |             | TOTAL   | 5,373,435 |                   |

1

Issuer name: Banco Santander, S.A. - LEI 5493006QMFDDMYWIAM13

Reference of the financial instrument: ordinary shares - Code ISIN ES0113900J37

Detailed information of the transactions carried out within the referred period is attached as Annex I.

Boadilla del Monte (Madrid), 4 September 2025

2

<div align='center'>ANNEX I</div>

Detailed information on each of the transactions carried out within the context of the Buy-back Programme between 28/08/2025 and 03/09/2025 (both inclusive)

(https://www.santander.com/content/dam/santander-com/es/documentos/cumplimiento/do-anexo-i-28-ago-a-03-09-2025.pdf)

3

<div align='center'>SIGNATURE</div>

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: | September 4, 2025 |     | Banco Santander, S.A. 
 By:                   | /s/ Pedro de Mingo Kaminouchi |                              |
|:------|:------------------|:----|:----------------------|:------------------------------|:-----------------------------|
|       |                   |     |                       | Name:                         | Pedro de Mingo Kaminouchi    |
|       |                   |     |                       | Title:                        | Head of Corporate Compliance |

September 4, 2025