v3.26.1
Investments - Summary of changes in investments (Details) - EUR (€)
€ in Millions
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Disclosure of associates [line items]      
Balance at beginning of year € 7,277 € 7,646 € 7,615
Acquisitions (disposals) of companies and capital increases (reductions) (17) 1,011 52
Changes in the consolidation method (Note 3) 15 (13) (43)
Entities for sale (Notes 3 y 12) (168) (1,137) 0
Effect of equity accounting 665 687 591
Dividends distributed and reimbursements of share premium (694) (745) (565)
Other global result 28 (32) (24)
Exchange differences and other changes (54) (140) 20
Balance at end of year 7,052 7,277 7,646
Zurich Santander Insurance America, S.L. - Consolidated      
Disclosure of associates [line items]      
Dividends distributed and reimbursements of share premium (206) (202) (202)
Metrovacesa, S.A.      
Disclosure of associates [line items]      
Dividends distributed and reimbursements of share premium (118) (52) (50)
Merlin Properties, SOCIMI, S.A.      
Disclosure of associates [line items]      
Dividends distributed and reimbursements of share premium (57) (53) (51)
CNP Santander      
Disclosure of associates [line items]      
Dividends distributed and reimbursements of share premium (54) (88) (51)
CIP S.A.      
Disclosure of associates [line items]      
Dividends distributed and reimbursements of share premium (16) (56) 0
Caceis (Notes 3 and 12)      
Disclosure of associates [line items]      
Dividends distributed and reimbursements of share premium 0 (114) 0
Hyundai Capital UK Limited      
Disclosure of associates [line items]      
Dividends distributed and reimbursements of share premium 0 € 0 (58)
Pluxee Beneficios Brasil, S.A.      
Disclosure of associates [line items]      
Percentage of voting equity interests acquired   20.00%  
Santander Vida Seguros y Reaseguros, S.A.      
Disclosure of associates [line items]      
Dividends distributed and reimbursements of share premium € (87) € (82) € (52)