v3.25.4
Fair values of financial instruments carried at fair value - Basis of valuing HSBC Holding's financial assets and liabilities measured at fair value (Details) - USD ($)
$ in Millions
Dec. 31, 2025
Dec. 31, 2024
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]    
Financial assets $ 3,117,161 $ 2,923,319
Financial liabilities 2,882,187 2,682,252
Financial liabilities designated at fair value    
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]    
Financial liabilities 158,456 138,727
Financial assets designated and otherwise mandatorily measured at fair value through profit or loss    
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]    
Financial assets 3,942 3,357
HSBC Holdings    
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]    
Financial assets 133,493 119,683
Financial liabilities 153,859 138,096
HSBC Holdings | Financial liabilities designated at fair value    
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]    
Financial liabilities 52,907 41,582
HSBC Holdings | Financial liabilities designated at fair value | Designated at fair value    
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]    
Financial liabilities 52,907 41,582
HSBC Holdings | Financial liabilities designated at fair value | Level 1 | Designated at fair value    
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]    
Financial liabilities 0 0
HSBC Holdings | Financial liabilities designated at fair value | Level 2 | Designated at fair value    
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]    
Financial liabilities 52,907 41,582
HSBC Holdings | Derivatives | Designated at fair value    
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]    
Financial liabilities 3,451 5,340
HSBC Holdings | Derivatives | Level 1 | Designated at fair value    
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]    
Financial liabilities 0 0
HSBC Holdings | Derivatives | Level 2 | Designated at fair value    
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]    
Financial liabilities 3,451 5,340
HSBC Holdings | Trading assets    
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]    
Financial assets 0 709
HSBC Holdings | Trading assets | Level 1    
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]    
Financial assets 0 709
HSBC Holdings | Trading assets | Level 2    
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]    
Financial assets 0 0
HSBC Holdings | Financial assets designated and otherwise mandatorily measured at fair value through profit or loss    
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]    
Financial assets 67,217 61,286
HSBC Holdings | Financial assets designated and otherwise mandatorily measured at fair value through profit or loss | Level 1    
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]    
Financial assets 0 0
HSBC Holdings | Financial assets designated and otherwise mandatorily measured at fair value through profit or loss | Level 2    
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]    
Financial assets 67,217 61,286
HSBC Holdings | Derivatives | Designated at fair value    
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]    
Financial assets 1,942 3,054
HSBC Holdings | Derivatives | Level 1 | Designated at fair value    
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]    
Financial assets 0 0
HSBC Holdings | Derivatives | Level 2 | Designated at fair value    
Disclosure Of Fair Value Measurement Of Assets And Liabilities [Line Items]    
Financial assets $ 1,942 $ 3,054