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 July, 2026
Commission File Number: 001-12518
Banco Santander, S.A.
(Exact name of registrant as specified in its
charter)
Ciudad Grupo Santander
28660 Boadilla del Monte (Madrid) Spain
(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
Banco Santander, S.A.
TABLE OF CONTENTS
Item
1
Report of Other Relevant Information dated July 23, 2026
Item
1
Banco Santander, S.A. (the “Bank”
or “Banco Santander”), in compliance with the Securities Market legislation, hereby communicates the following:
OTHER RELEVANT INFORMATION
Reference is made
to our notice of inside information of 4 February 2026 (official registry number 3077) (the “Buyback Commencement Communication”),
relating to the buyback programme of own shares (the “Buyback Programme”) approved by the Board of Directors of Banco
Santander.
Pursuant to article 5 of Regulation (EU) no. 596/2014
on Market Abuse of 16 April 2014, and articles 2.2 and 2.3 of Commission Delegated Regulation (EU) 2016/1052, of 8 March 2016, the Bank
informs of the transactions carried out over its own shares between 16 and 22 July (both inclusive).
The cash amount of the shares purchased to 22 July
2026 as a result of the execution of the Buyback Programme amounts to 4,053,401,441 Euros, which represents approximately 80.6% of the
maximum investment amount of the Buyback Programme. The programme was announced together with its other characteristics through the Buyback
Commencement Communication. With these purchases, the Bank has repurchased approximately 17.5% of its outstanding shares as of 2021.
Date
Security
Transaction
Trading venue
Number of shares
Weighted average price (€)
16/07/2026
SAN
Purchase
XMAD
3,000,000
11.9071
17/07/2026
SAN
Purchase
XMAD
2,000,000
11.7786
17/07/2026
SAN
Purchase
CEUX
1,000,000
11.7789
20/07/2026
SAN
Purchase
XMAD
2,000,000
11.7882
20/07/2026
SAN
Purchase
CEUX
1,000,000
11.7868
21/07/2026
SAN
Purchase
XMAD
2,000,000
11.8508
22/07/2026
SAN
Purchase
XMAD
1,000,000
12.1261
22/07/2026
SAN
Purchase
CEUX
1,000,000
12.1260
TOTAL
13,000,000
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), 23 July 2026
ANNEX I
Detailed information on each of the transactions
carried out within the context of the Buy-back Programme between 16/07/2026 and 22/07/2026 (both inclusive)
(https://www.santander.com/content/dam/santander-com/es/documentos/cumplimiento/do-anexo-i-16-a-22-julio-2026-es.pdf)
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.
Banco Santander, S.A.
Date:
July 23, 2026
By:
/s/ Pedro de Mingo Kaminouchi
Name:
Pedro de Mingo Kaminouchi
Title:
Head of Corporate Compliance