v3.25.2
Fair value of financial instruments - Unrealised gains and losses recognised in the period on Level 3 assets and liabilities held at period end (Details) - GBP (£)
£ in Millions
6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Disclosure of detailed information about financial instruments [line items]    
Trading income £ 4,358 £ 3,302
Other income 29 14
Other comprehensive income 151 (1,121)
Significant unobservable inputs (Level 3)    
Disclosure of detailed information about financial instruments [line items]    
Trading income 192 (192)
Other income 9 41
Other comprehensive income 0 0
Total 201 (151)
Significant unobservable inputs (Level 3) | Investment property    
Disclosure of detailed information about financial instruments [line items]    
Trading income 0 0
Other income 0 0
Other comprehensive income 0 0
Total 0 0
Significant unobservable inputs (Level 3) | Net derivative financial instruments    
Disclosure of detailed information about financial instruments [line items]    
Trading income 165 (191)
Other income 1 0
Other comprehensive income 0 0
Total 166 (191)
Trading portfolio liabilities | Significant unobservable inputs (Level 3)    
Disclosure of detailed information about financial instruments [line items]    
Trading income 34 17
Other income 0 0
Other comprehensive income 0 0
Total 34 17
Financial liabilities designated at fair value | Significant unobservable inputs (Level 3)    
Disclosure of detailed information about financial instruments [line items]    
Trading income 86 (29)
Other income 0 0
Other comprehensive income 0 0
Total 86 (29)
Trading portfolio assets | Significant unobservable inputs (Level 3)    
Disclosure of detailed information about financial instruments [line items]    
Trading income 21 (2)
Other income 0 0
Other comprehensive income 0 0
Total 21 (2)
Financial assets at fair value through the income statement | Significant unobservable inputs (Level 3)    
Disclosure of detailed information about financial instruments [line items]    
Trading income (117) 15
Other income (20) 30
Other comprehensive income 0 0
Total (137) 45
Financial assets at fair value through other comprehensive income | Significant unobservable inputs (Level 3)    
Disclosure of detailed information about financial instruments [line items]    
Trading income 3 (2)
Other income 28 11
Other comprehensive income 0 0
Total £ 31 £ 9