Banco Santander S A : communicates the transactions over its own shares which it has carried out between 15th October and 21st October under the buyback programme

Banco Santander, S.A., in compliance with the Securities Market legislation, hereby communicates the following:

OTHER RELEVANT INFORMATION

Reference is made to our notice of inside information of 6 October, 2021 (official registry number 1086), relating to the buyback programme of own shares (the "Buy-backProgramme") approved by the Board of Directors of Banco Santander, S.A. 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, Banco Santander, S.A. informs -on the basis of the information received from Morgan Stanley Europe SE as intermediary in charge of executing the Buy-back Programme- that it has carried out the following transactions over its own shares between 15 October and 21 October, 2021 (both included):

Date	Security		Transaction	Trading venue	Number of	Weighted
					shares	average price
						(€)
15/10/2021	SAN.MC		Purchase	XMAD	5,005,509	€3.3447
18/10/2021	SAN.MC		Purchase	XMAD	5,264,921	€3.3429
19/10/2021	SAN.MC		Purchase	XMAD	5,572,314	€3.3577
20/10/2021	SAN.MC		Purchase	XMAD	5,773,023	€3.3496
21/10/2021	SAN.MC		Purchase	XMAD	6,599,265	€3.3242
		TOTAL		28,215,032

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), 22 October 2021

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ANNEX I

Detailed information on each of the transactions carried out within the context of the Buy-back Programme between 15 October and 21 October 2021 (both included)

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