v3.26.1
Trading derivatives (assets and liabilities) and short positions - Schedule of short positions (Details) - EUR (€)
€ in Millions
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Financial instruments      
FINANCIAL LIABILITIES HELD FOR TRADING € 171,546 € 152,151 € 122,270
Short positions      
Financial instruments      
FINANCIAL LIABILITIES HELD FOR TRADING 44,015 35,830 26,174
Debt securities | Short positions      
Financial instruments      
Borrowed securities 2,938 2,566 3,263
Short sales 40,387 32,726 22,365
Debt securities | Short positions | Banco Santander México, S.A., Institución de Banca Múltiple, Grupo Financiero Santander México      
Financial instruments      
Borrowed securities 1,358 1,199 1,881
Debt securities | Short positions | Banco Santander (Brasil) S.A.      
Financial instruments      
Short sales 7,417 5,950 3,462
Debt securities | Short positions | Santander US Capital Markets LLC      
Financial instruments      
Short sales 3,396 2,382 2,442
Equity instruments | Short positions      
Financial instruments      
Borrowed securities 690 538 546
Banco Santander, S.A. | Debt securities | Short positions      
Financial instruments      
Borrowed securities 1,555 1,347 1,383
Short sales 28,710 23,813 16,143
Banco Santander, S.A. | Equity instruments | Short positions      
Financial instruments      
Borrowed securities € 429 € 358 € 312