v3.26.1
Loans and advances to customers - Schedule of changes in loss allowance and gross carrying amount (Details) - EUR (€)
€ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items]      
Impairment at beginning of year € (283,497) € (243,203)  
Impairment at end of year (300,026) (283,497) € (243,203)
Customers      
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items]      
Impairment at beginning of year (1,054,069) (1,036,349)  
Impairment at end of year (1,037,288) (1,054,069) (1,036,349)
Customers | Financial instruments credit-impaired      
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items]      
Write-offs 13,266 13,212 13,847
Exchange differences and other changes 2,536 947 (168)
Accumulated impairment      
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items]      
Impairment at beginning of year 349 286  
Impairment at end of year 520 349 286
Accumulated impairment | Customers      
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items]      
Impairment at beginning of year 22,125 22,788  
Impairment at end of year 21,158 22,125 22,788
Financial assets at amortised cost and financial assets at fair value through other comprehensive income | Accumulated impairment      
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items]      
Impairment at beginning of year 22,125 22,788 22,684
Write-offs (13,266) (13,212) (13,847)
Exchange differences and other changes (1,845) (879) 194
Impairment at end of year 21,158 22,125 22,788
Financial assets at amortised cost and financial assets at fair value through other comprehensive income | Accumulated impairment | Financial instruments not credit-impaired      
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items]      
Impairment at beginning of year 8,037 8,550  
Impairment at end of year 7,631 8,037 8,550
Financial assets at amortised cost and financial assets at fair value through other comprehensive income | Accumulated impairment | Financial instruments credit-impaired      
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items]      
Impairment at beginning of year 14,088 14,238  
Impairment at end of year 13,527 14,088 14,238
Financial assets at amortised cost and financial assets at fair value through other comprehensive income | Accumulated impairment | Customers      
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items]      
Impairment at beginning of year 22,125 22,788 22,684
To stage 2 from stage 1 1,887 2,050 2,258
To stage 3 from stage 1 4,230 4,163 3,873
To stage 3 from stage 2 1,571 1,853 1,901
To stage 1 from stage 2 (384) (616) (756)
To stage 3 from stage 2 (167) (415) (638)
To stage 1 from stage 3 (43) (133) (157)
Net changes of the exposure and modifications in the credit risk 7,050 6,706 7,530
Write-offs (13,266) (13,212) (13,847)
Exchange differences and other changes (1,845) (1,059) (60)
Impairment at end of year 21,158 22,125 22,788
Financial assets at amortised cost and financial assets at fair value through other comprehensive income | Accumulated impairment | Customers | Financial instruments not credit-impaired | Stage 1      
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items]      
Impairment at beginning of year 3,293 3,596 3,626
To stage 2 from stage 1 (847) (626) (696)
To stage 3 from stage 1 (701) (385) (405)
To stage 1 from stage 2 82 109 149
To stage 1 from stage 3 16 23 27
Net changes of the exposure and modifications in the credit risk 1,269 755 875
Exchange differences and other changes (112) (179) 20
Impairment at end of year 3,000 3,293 3,596
Financial assets at amortised cost and financial assets at fair value through other comprehensive income | Accumulated impairment | Customers | Financial instruments not credit-impaired | Stage 2 and 3      
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items]      
Impairment at beginning of year 4,744 4,954 5,127
To stage 2 from stage 1 2,734 2,676 2,954
To stage 3 from stage 2 (1,189) (1,591) (1,820)
To stage 1 from stage 2 (466) (725) (905)
To stage 3 from stage 2 177 278 282
Net changes of the exposure and modifications in the credit risk (800) (704) (557)
Exchange differences and other changes (569) (144) (127)
Impairment at end of year 4,631 4,744 4,954
Financial assets at amortised cost and financial assets at fair value through other comprehensive income | Accumulated impairment | Customers | Financial instruments credit-impaired | Stage 2 and 3      
Disclosure of reconciliation of changes in loss allowance and explanation of changes in gross carrying amount for financial instruments [line items]      
Impairment at beginning of year 14,088 14,238 13,931
To stage 3 from stage 1 4,931 4,548 4,278
To stage 3 from stage 2 2,760 3,444 3,721
To stage 3 from stage 2 (344) (693) (920)
To stage 1 from stage 3 (59) (156) (184)
Net changes of the exposure and modifications in the credit risk 6,581 6,655 7,212
Write-offs (13,266) (13,212) (13,847)
Exchange differences and other changes (1,164) (736) 47
Impairment at end of year € 13,527 € 14,088 € 14,238