v3.26.1
Fair value of assets and liabilities - Changes in level 3 financial assets (Details) - EUR (€)
€ in Millions
6 Months Ended 12 Months Ended
Jun. 30, 2026
Dec. 31, 2025
Financial assets at fair value, class    
Disclosure of fair value measurement of assets [line items]    
Unrealised gains on (losses) recognised in the statement of profit or loss € 199 € 280
Level 3    
Disclosure of fair value measurement of assets [line items]    
Opening balance as at 1 January 11,742 11,005
Realised gain/loss recognised in the statement of profit or loss during the period (199) (278)
Revaluation recognised in other comprehensive income during the period 20 8
Purchase of assets 2,953 7,520
Sale of assets (1,784) (3,197)
Maturity/settlement (335) (1,057)
Reclassifications (242) 28
Transfers into Level 3 107 1,139
Transfers out of Level 3 (1,418) (3,372)
Exchange rate differences 7 (53)
Changes in the composition of the group and other changes 3 0
Closing balance 10,854 11,742
Level 3 | Financial assets mandatorily at FVPL    
Disclosure of fair value measurement of assets [line items]    
Opening balance as at 1 January 7,625 5,721
Realised gain/loss recognised in the statement of profit or loss during the period 36 211
Purchase of assets 2,343 5,177
Sale of assets (1,723) (1,765)
Maturity/settlement (53) (166)
Reclassifications (242) 18
Transfers into Level 3 89 824
Transfers out of Level 3 (1,011) (2,389)
Exchange rate differences 2 (6)
Changes in the composition of the group and other changes 2 0
Closing balance 7,070 7,625
Level 3 | Financial assets designated at FVPL    
Disclosure of fair value measurement of assets [line items]    
Opening balance as at 1 January 2,576 4,121
Realised gain/loss recognised in the statement of profit or loss during the period (250) (798)
Purchase of assets 565 1,208
Sale of assets 0 (1,160)
Maturity/settlement (141) (763)
Reclassifications 0 0
Transfers into Level 3 0 0
Transfers out of Level 3 (18) 0
Exchange rate differences 5 (33)
Changes in the composition of the group and other changes 1 0
Closing balance 2,738 2,576
Level 3 | Financial assets at FVOCI    
Disclosure of fair value measurement of assets [line items]    
Opening balance as at 1 January 307 270
Revaluation recognised in other comprehensive income during the period 20 8
Purchase of assets 12 182
Sale of assets (1) (163)
Maturity/settlement 0 0
Reclassifications 0 10
Transfers into Level 3 13 0
Transfers out of Level 3 0 0
Exchange rate differences (1) 0
Changes in the composition of the group and other changes 0 0
Closing balance 350 307
Level 3 | Trading assets    
Disclosure of fair value measurement of assets [line items]    
Opening balance as at 1 January 1,114 824
Realised gain/loss recognised in the statement of profit or loss during the period 15 247
Purchase of assets 33 953
Sale of assets (60) (109)
Maturity/settlement (142) (128)
Reclassifications 120 0
Transfers into Level 3 4 316
Transfers out of Level 3 (389) (974)
Exchange rate differences 0 (14)
Changes in the composition of the group and other changes 0 0
Closing balance 695 1,114
Level 3 | Non-trading derivatives    
Disclosure of fair value measurement of assets [line items]    
Opening balance as at 1 January 121 68
Realised gain/loss recognised in the statement of profit or loss during the period (1) 63
Purchase of assets 0 0
Sale of assets 0 0
Maturity/settlement 0 0
Reclassifications (120) (1)
Transfers into Level 3 0 0
Transfers out of Level 3 0 (9)
Exchange rate differences 0 0
Changes in the composition of the group and other changes 0 0
Closing balance € 0 € 121