v3.25.4
Employee compensation and benefits - Fair value of plan assets by asset classes (Details) - Pension Plan - USD ($)
$ in Millions
Dec. 31, 2025
Dec. 31, 2024
Principal plan    
Disclosure of fair value of plan assets [line items]    
Fair value of plan assets $ 25,023 $ 23,652
– equities 58 65
– derivatives 300 295
– property 855 833
– pooled investment vehicles 9,549 8,064
– other 434 278
Principal plan | – bonds fixed income    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 5,964 5,864
Principal plan | – bonds index-linked    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 7,863 8,253
Principal plan | – bonds other    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 0 0
Principal plan | HSBC Bank plc    
Disclosure of fair value of plan assets [line items]    
Fair value of plan assets 350 421
– equities 0 0
– derivatives 350 421
– property 0 0
– pooled investment vehicles 0 0
– other 0 0
Principal plan | HSBC Bank plc | – bonds fixed income    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 0 0
Principal plan | HSBC Bank plc | – bonds index-linked    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 0 0
Principal plan | HSBC Bank plc | – bonds other    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 0 0
Other plans    
Disclosure of fair value of plan assets [line items]    
Fair value of plan assets 7,329 7,106
– equities 608 587
– derivatives (61) 2
– property 140 103
– other 2,292 2,237
Other plans | – bonds fixed income    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 3,742 3,671
Other plans | – bonds index-linked    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 47 33
Other plans | – bonds other    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 561 473
Other plans | HSBC Bank plc    
Disclosure of fair value of plan assets [line items]    
Fair value of plan assets 16 19
– equities 4 4
– derivatives 0 0
– property 0 0
– other 9 11
Other plans | HSBC Bank plc | – bonds fixed income    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 3 4
Other plans | HSBC Bank plc | – bonds index-linked    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 0 0
Other plans | HSBC Bank plc | – bonds other    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 0 0
Quoted market price in active market | Principal plan    
Disclosure of fair value of plan assets [line items]    
Fair value of plan assets 13,768 13,903
– equities 0 0
– derivatives 0 0
– property 0 0
– pooled investment vehicles 0 0
– other 434 278
Quoted market price in active market | Principal plan | – bonds fixed income    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 5,471 5,372
Quoted market price in active market | Principal plan | – bonds index-linked    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 7,863 8,253
Quoted market price in active market | Principal plan | – bonds other    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 0 0
Quoted market price in active market | Other plans    
Disclosure of fair value of plan assets [line items]    
Fair value of plan assets 5,717 6,407
– equities 608 587
– derivatives 0 (3)
– property 135 98
– other 652 1,548
Quoted market price in active market | Other plans | – bonds fixed income    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 3,741 3,671
Quoted market price in active market | Other plans | – bonds index-linked    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 47 33
Quoted market price in active market | Other plans | – bonds other    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 534 473
No quoted market price in active market | Principal plan    
Disclosure of fair value of plan assets [line items]    
Fair value of plan assets 11,255 9,749
– equities 58 65
– derivatives 300 295
– property 855 833
– pooled investment vehicles 9,549 8,064
– other 0 0
No quoted market price in active market | Principal plan | – bonds fixed income    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 493 492
No quoted market price in active market | Principal plan | – bonds index-linked    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 0 0
No quoted market price in active market | Principal plan | – bonds other    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 0 0
No quoted market price in active market | Other plans    
Disclosure of fair value of plan assets [line items]    
Fair value of plan assets 1,612 699
– equities 0 0
– derivatives (61) 5
– property 5 5
– other 1,640 689
No quoted market price in active market | Other plans | – bonds fixed income    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 1 0
No quoted market price in active market | Other plans | – bonds index-linked    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income 0 0
No quoted market price in active market | Other plans | – bonds other    
Disclosure of fair value of plan assets [line items]    
– bonds fixed income $ 27 $ 0