v3.26.1
Fair values of financial assets and liabilities- Schedule of Movements in Level 3 Financial Assets Portfolio (Details) - GBP (£)
£ in Millions
 6 Months Ended
Jun. 30, 2026
Dec. 31, 2025
Jun. 30, 2025
Reconciliation of changes in fair value measurement, assets [abstract]      
Gains recognised in other comprehensive income within the revaluation reserve in respect of financial assets at FVOCI £ 0 £ (8) [1] £ 42 [1]
Level 3      
Reconciliation of changes in fair value measurement, assets [abstract]      
Balance at beginning of period 10,816 10,656 11,003
Increase (decrease) through foreign exchange and other movements, financial assets (2)   13
Gains recognised in the income statement within other income 221   61
Gains recognised in other comprehensive income within the revaluation reserve in respect of financial assets at FVOCI 1   42
Purchases/increases 525   145
Sales/repayments (1,111)   (488)
Transfers into the level 3 portfolio 16   13
Transfers out of the level 3 portfolio (14)   (133)
Balance at end of period 10,452 10,816 10,656
Level 3 | Financial assets at fair value through profit or loss      
Reconciliation of changes in fair value measurement, assets [abstract]      
Balance at beginning of period 10,251 9,700 9,889
Increase (decrease) through foreign exchange and other movements, financial assets 0   (1)
Gains recognised in the income statement within other income 191   213
Gains recognised in other comprehensive income within the revaluation reserve in respect of financial assets at FVOCI 0   0
Purchases/increases 522   137
Sales/repayments (1,096)   (482)
Transfers into the level 3 portfolio 16   12
Transfers out of the level 3 portfolio (14)   (68)
Balance at end of period 9,870 10,251 9,700
Gains (losses) recognised in the income statement, within other income, relating to the change in fair value of those assets held 147   120
Level 3 | Financial assets at fair value through other comprehensive income      
Reconciliation of changes in fair value measurement, assets [abstract]      
Balance at beginning of period 101 417 373
Increase (decrease) through foreign exchange and other movements, financial assets 0   2
Gains recognised in the income statement within other income 1   2
Gains recognised in other comprehensive income within the revaluation reserve in respect of financial assets at FVOCI 1   42
Purchases/increases 1   0
Sales/repayments (3)   (2)
Transfers into the level 3 portfolio 0   0
Transfers out of the level 3 portfolio 0   0
Balance at end of period 101 101 417
Gains (losses) recognised in the income statement, within other income, relating to the change in fair value of those assets held 1   3
Level 3 | Derivative financial assets      
Reconciliation of changes in fair value measurement, assets [abstract]      
Balance at beginning of period 464 539 741
Increase (decrease) through foreign exchange and other movements, financial assets (2)   12
Gains recognised in the income statement within other income 29   (154)
Gains recognised in other comprehensive income within the revaluation reserve in respect of financial assets at FVOCI 0   0
Purchases/increases 2   8
Sales/repayments (12)   (4)
Transfers into the level 3 portfolio 0   1
Transfers out of the level 3 portfolio 0   (65)
Balance at end of period 481 £ 464 539
Gains (losses) recognised in the income statement, within other income, relating to the change in fair value of those assets held 44   (124)
Level 3 | Total financial assets carried at fair value £m      
Reconciliation of changes in fair value measurement, assets [abstract]      
Gains (losses) recognised in the income statement, within other income, relating to the change in fair value of those assets held £ 192   £ (1)
[1] 1Current tax and deferred tax impacts, previously shown in aggregate for each reserve, are now presented alongside each line
item. Comparatives are represented on a consistent basis.