Goodwill and intangible assets - Disclosure of goodwill allocated to business operations according to business segments (Details) - GBP (£) £ in Millions	Dec. 31, 2025	Dec. 31, 2024
Disclosure of reconciliation of changes in intangible assets and goodwill [line items]
Goodwill	£ 509	£ 539
Barclays Private Bank and Wealth Management
Disclosure of reconciliation of changes in intangible assets and goodwill [line items]
Goodwill	95	95
Barclays US Consumer Bank
Disclosure of reconciliation of changes in intangible assets and goodwill [line items]
Goodwill	£ 414	£ 444

The amount of assets representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognised. [Refer: Total for all business combinations [member]]

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+ Details