Pensions and other post-retirement benefit obligations - Schedule of defined benefit plan recognised in balance sheet (Details) - GBP (£) £ in Millions |
Sep. 30, 2025 |
Mar. 31, 2025 |
Sep. 30, 2024 |
Mar. 31, 2024 |
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| Disclosure of defined benefit plans [line items] | ||||
| Other post-employment liabilities | £ (44) | £ (47) | ||
| Net defined benefit liability (asset) including restrictions on assets recognized | 2,296 | 1,993 | ||
| Restrictions on asset recognised | (221) | (77) | ||
| Net defined benefit asset | 2,075 | 1,916 | £ 1,875 | £ 1,814 |
| Assets | 2,424 | 2,489 | ||
| Liabilities | (349) | (573) | ||
| Funded obligations | ||||
| Disclosure of defined benefit plans [line items] | ||||
| Present value of obligations | (15,628) | (16,154) | ||
| Fair value of plan assets | 18,218 | 18,441 | ||
| Funding surplus/(deficit) | 2,590 | 2,287 | ||
| Unfunded obligations | ||||
| Disclosure of defined benefit plans [line items] | ||||
| Present value of obligations | £ (250) | £ (247) |
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- Definition The present value, without deducting any plan assets, of expected future payments required to settle the obligation resulting from employee service in the current and prior periods. [Refer: Plan assets, at fair value] Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table. No definition available.
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- Definition The amount of deficit or surplus in a defined benefit plan, adjusted for any effect of limiting a net defined benefit asset to the asset ceiling. [Refer: Defined benefit plans [domain]] Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The fair value of defined benefit plan assets. Plan assets comprise assets held by a long-term employee benefit fund and qualifying insurance policies. [Refer: At fair value [member]] Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The amount of surplus in a defined benefit plan, adjusted for any effect of limiting a net defined benefit asset to the asset ceiling. [Refer: Defined benefit plans [domain]] Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The amount of deficit in a defined benefit plan. [Refer: Defined benefit plans [domain]] Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The fair value of any plan assets, less the present value of the defined benefit obligation. [Refer: Plan assets [member]] Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Irrecoverable Surplus, Restrictions On Assets Recognized No definition available.
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- Definition Net Defined Benefit Liability (Asset) Including Restrictions On Assets Recognized No definition available.
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- Definition Other Post-Employment Liabilities No definition available.
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- Details
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- Details
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