v3.25.4
Risk Management - Disclosure of functional currency of the operation (Details) - GBP (£)
£ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Disclosure of risk management strategy related to hedge accounting [line items]    
Financial instrument which hedge net investments £ 10,400 £ 11,600
Foreign exchange risk    
Disclosure of risk management strategy related to hedge accounting [line items]    
Foreign currency net investments 39,763 41,366
Borrowings which hedge the net investments (6,109) (7,588)
Derivatives which hedge the net investments (4,319) (4,013)
Structural currency exposures pre- economic hedges 29,335 29,764
Other Equity instruments (7,887) (6,960)
Remaining structural currency exposures 21,448 22,805
Decrease in structural currency exposures, net of hedging instruments 1,400  
Increase (decrease) in foreign currency net investments (1,600)  
Decrease in financial instruments which hedge net investments 1,200  
USD    
Disclosure of risk management strategy related to hedge accounting [line items]    
Foreign currency net investments 25,531 27,742
Borrowings which hedge the net investments (2,914) (4,644)
Derivatives which hedge the net investments (2,141) (2,229)
Structural currency exposures pre- economic hedges 20,476 20,868
Other Equity instruments (5,450) (5,846)
Remaining structural currency exposures 15,026 15,023
Increase (decrease) in foreign currency net investments (2,200)  
EUR    
Disclosure of risk management strategy related to hedge accounting [line items]    
Foreign currency net investments 10,195 9,559
Borrowings which hedge the net investments (3,018) (2,729)
Derivatives which hedge the net investments 0 0
Structural currency exposures pre- economic hedges 7,177 6,830
Other Equity instruments (1,310) (265)
Remaining structural currency exposures 5,867 6,565
Increase (decrease) in foreign currency net investments 600  
INR    
Disclosure of risk management strategy related to hedge accounting [line items]    
Foreign currency net investments 1,486 1,400
Borrowings which hedge the net investments 0 0
Derivatives which hedge the net investments (1,260) (992)
Structural currency exposures pre- economic hedges 226 408
Other Equity instruments 0 0
Remaining structural currency exposures 226 408
JPY    
Disclosure of risk management strategy related to hedge accounting [line items]    
Foreign currency net investments 544 628
Borrowings which hedge the net investments (177) (215)
Derivatives which hedge the net investments 0 0
Structural currency exposures pre- economic hedges 367 413
Other Equity instruments 0 0
Remaining structural currency exposures 367 413
Other    
Disclosure of risk management strategy related to hedge accounting [line items]    
Foreign currency net investments 2,007 2,037
Borrowings which hedge the net investments 0 0
Derivatives which hedge the net investments (918) (792)
Structural currency exposures pre- economic hedges 1,089 1,245
Other Equity instruments (1,127) (849)
Remaining structural currency exposures £ (38) £ 396