v3.26.1
Fair value of assets and liabilities - Methods applied in determining fair values of financial assets and liabilities (carried at amortised cost) (Details) - EUR (€)
€ in Millions
Jun. 30, 2026
Dec. 31, 2025
Disclosure of fair value measurement of assets and liabilities [Line Items]    
Loans and advances to banks € 30,311 € 21,204
Loans and advances to customers 761,314 727,733
Deposits from banks 31,687 18,517
Customer deposits 773,291 721,373
Debt securities in issue 166,011 151,231
Subordinated loans 19,068 18,100
Financial liabilities    
Disclosure of fair value measurement of assets and liabilities [Line Items]    
Deposits from banks 31,437 18,308
Customer deposits 773,040 721,097
Debt securities in issue 167,205 152,391
Subordinated loans 19,701 18,722
Financial liabilities 991,384 910,519
Financial liabilities | Level 1    
Disclosure of fair value measurement of assets and liabilities [Line Items]    
Deposits from banks
Customer deposits
Debt securities in issue 88,219 84,506
Subordinated loans 19,350 18,368
Financial liabilities 107,568 102,874
Financial liabilities | Level 2    
Disclosure of fair value measurement of assets and liabilities [Line Items]    
Deposits from banks 19,245 9,162
Customer deposits 112,052 82,665
Debt securities in issue 73,469 64,028
Subordinated loans 352 354
Financial liabilities 205,118 156,208
Financial liabilities | Level 3    
Disclosure of fair value measurement of assets and liabilities [Line Items]    
Deposits from banks 3,553 3,745
Customer deposits 18,834 17,433
Debt securities in issue 5,517 3,857
Subordinated loans
Financial liabilities 27,904 25,035
Financial liabilities | Carrying Amount    
Disclosure of fair value measurement of assets and liabilities [Line Items]    
Deposits from banks 31,687 18,517
Customer deposits 773,291 721,373
Debt securities in issue 166,011 151,231
Subordinated loans 19,068 18,100
Financial liabilities 990,057 909,221
Financial liabilities | Carrying amount presented as fair value    
Disclosure of fair value measurement of assets and liabilities [Line Items]    
Deposits from banks 8,639 5,401
Customer deposits 642,155 620,999
Debt securities in issue
Subordinated loans
Financial liabilities 650,794 626,401
Financial Assets    
Disclosure of fair value measurement of assets and liabilities [Line Items]    
Loans and advances to banks 30,257 21,141
Loans and advances to customers 742,158 709,405
Securities at amortised cost 67,017 52,796
Financial assets 839,432 783,342
Financial Assets | Level 1    
Disclosure of fair value measurement of assets and liabilities [Line Items]    
Loans and advances to banks
Loans and advances to customers
Securities at amortised cost 60,198 47,722
Financial assets 60,198 47,722
Financial Assets | Level 2    
Disclosure of fair value measurement of assets and liabilities [Line Items]    
Loans and advances to banks 23,007 14,722
Loans and advances to customers 14,379 12,782
Securities at amortised cost 4,006 2,381
Financial assets 41,393 29,885
Financial Assets | Level 3    
Disclosure of fair value measurement of assets and liabilities [Line Items]    
Loans and advances to banks 3,759 3,366
Loans and advances to customers 707,470 678,392
Securities at amortised cost 2,813 2,692
Financial assets 714,042 684,450
Financial Assets | Carrying Amount    
Disclosure of fair value measurement of assets and liabilities [Line Items]    
Loans and advances to banks 30,311 21,204
Loans and advances to customers 761,314 727,733
Securities at amortised cost 67,985 53,867
Financial assets 859,610 802,804
Financial Assets | Carrying amount presented as fair value    
Disclosure of fair value measurement of assets and liabilities [Line Items]    
Loans and advances to banks 3,491 3,053
Loans and advances to customers 20,308 18,231
Securities at amortised cost
Financial assets € 23,799 € 21,284