v3.25.2
Fair value of financial instruments - Assets and liabilities held at fair value disaggregated by valuation technique (fair value hierarchy) and balance sheet classification (Details) - GBP (£)
£ in Millions
Jun. 30, 2025
Dec. 31, 2024
Disclosure of detailed information about financial instruments [line items]    
Trading portfolio assets £ 187,223 £ 166,453
Financial assets at fair value through the income statement 218,552 193,734
Derivative financial instruments 280,194 293,530
Financial assets at fair value through other comprehensive income 77,311 78,059
Trading portfolio liabilities (69,305) (56,908)
Financial liabilities designated at fair value (317,485) (282,224)
Derivative financial instruments (265,376) (279,415)
Fair value    
Disclosure of detailed information about financial instruments [line items]    
Trading portfolio assets 187,223 166,453
Financial assets at fair value through the income statement 218,552 193,734
Derivative financial instruments 280,194 293,530
Financial assets at fair value through other comprehensive income 77,311 78,059
Investment property 42 9
Total assets 763,322 731,785
Trading portfolio liabilities (69,305) (56,908)
Financial liabilities designated at fair value (317,485) (282,224)
Derivative financial instruments (265,376) (279,415)
Total liabilities (652,166) (618,547)
Quoted market prices (Level 1) | Fair value    
Disclosure of detailed information about financial instruments [line items]    
Trading portfolio assets 87,555 77,761
Financial assets at fair value through the income statement 7,702 3,526
Derivative financial instruments 108 101
Financial assets at fair value through other comprehensive income 24,755 25,913
Investment property 0 0
Total assets 120,120 107,301
Trading portfolio liabilities (39,606) (27,694)
Financial liabilities designated at fair value (1,576) (181)
Derivative financial instruments (93) (86)
Total liabilities (41,275) (27,961)
Observable inputs (Level 2) | Fair value    
Disclosure of detailed information about financial instruments [line items]    
Trading portfolio assets 89,789 78,577
Financial assets at fair value through the income statement 202,019 181,784
Derivative financial instruments 278,097 291,352
Financial assets at fair value through other comprehensive income 49,378 48,407
Investment property 0 0
Total assets 619,283 600,120
Trading portfolio liabilities (29,275) (28,819)
Financial liabilities designated at fair value (313,061) (278,785)
Derivative financial instruments (262,422) (276,148)
Total liabilities (604,758) (583,752)
Significant unobservable inputs (Level 3)    
Disclosure of detailed information about financial instruments [line items]    
Trading portfolio assets 9,879 10,115
Financial assets at fair value through the income statement 8,831 8,424
Derivative financial instruments 1,989 2,077
Financial assets at fair value through other comprehensive income 3,178 3,739
Investment property 42 9
Total assets 23,919 24,364
Trading portfolio liabilities (424) (395)
Financial liabilities designated at fair value (2,848) (3,258)
Derivative financial instruments (2,861) (3,181)
Total liabilities (6,133) (6,834)
Significant unobservable inputs (Level 3) | Fair value    
Disclosure of detailed information about financial instruments [line items]    
Trading portfolio assets 9,879 10,115
Financial assets at fair value through the income statement 8,831 8,424
Derivative financial instruments 1,989 2,077
Financial assets at fair value through other comprehensive income 3,178 3,739
Investment property 42 9
Total assets 23,919 24,364
Trading portfolio liabilities (424) (395)
Financial liabilities designated at fair value (2,848) (3,258)
Derivative financial instruments (2,861) (3,181)
Total liabilities £ (6,133) £ (6,834)