Retirement benefits (Details) £ in Millions |
Jun. 30, 2026
GBP (£)
section
|
Dec. 31, 2025
GBP (£)
|
Sep. 30, 2025
GBP (£)
|
|---|---|---|---|
| Disclosure of fair value of plan assets [line items] | |||
| Surplus (deficit) in plan | £ 3,100 | £ 3,000 | |
| Number of Sections of The UK Retirement Fund (UKRF) | section | 2 | ||
| Pension defined benefit plans | Defined benefit plans other than multi-employer plans, state plans and plans that share risks between entities under common control | Country of domicile | |||
| Disclosure of fair value of plan assets [line items] | |||
| Surplus (deficit) in plan | £ 3,200 | £ 3,300 | |
| Pension defined benefit plans | Barclays Bank PLC | Country of domicile | |||
| Disclosure of fair value of plan assets [line items] | |||
| Surplus (deficit) in plan | £ 1,900 | ||
| Pension defined benefit plans | Barclays UK | Country of domicile | |||
| Disclosure of fair value of plan assets [line items] | |||
| Surplus (deficit) in plan | £ 83 |