v3.25.2
Derivative financial instruments - Narrative (Details) - GBP (£)
£ in Billions
6 Months Ended 12 Months Ended
Jun. 30, 2025
Dec. 31, 2024
Derivative financial liabilities    
Disclosure of offsetting of financial assets [line items]    
Gross financial assets set off against financial liabilities subject to offsetting, enforceable master netting arrangements or similar agreements £ 43 £ 46
Derivative liability exposures 240 254
Non-cash assets pledged as collateral 5 5
Cash collateral netted | Derivative financial liabilities    
Disclosure of offsetting of financial assets [line items]    
Gross financial assets set off against financial liabilities subject to offsetting, enforceable master netting arrangements or similar agreements 4 6
Derivative liability exposures 23 23
Derivative financial assets    
Disclosure of offsetting of financial assets [line items]    
Gross financial liabilities set off against financial assets subject to offsetting, enforceable master netting arrangements or similar agreements 43 47
Derivative asset exposures 248 261
Non-cash collateral 13 13
Derivative financial assets | Cash collateral netted    
Disclosure of offsetting of financial assets [line items]    
Gross financial liabilities set off against financial assets subject to offsetting, enforceable master netting arrangements or similar agreements 5 5
Derivative asset exposures £ 32 £ 31