v3.25.3
Assets held for sale - Schedule of assets and liabilities classified as held for sale (Details) - GBP (£)
£ in Millions
Sep. 30, 2025
Mar. 31, 2025
Disclosure Of Detailed Information About Assets Held For Sale [Line Items]    
Assets held for sale £ 1,146 £ 2,628
Liabilities held for sale (328) (434)
Assets and liabilities classified as held for sale    
Disclosure Of Detailed Information About Assets Held For Sale [Line Items]    
Assets held for sale 1,146 2,628
Liabilities held for sale (328) (434)
Net assets / (liabilities) held for sale 818 2,194
National Grid Renewables | Assets and liabilities classified as held for sale    
Disclosure Of Detailed Information About Assets Held For Sale [Line Items]    
Assets held for sale 0 1,528
Liabilities held for sale 0 (108)
Net assets / (liabilities) held for sale 0 1,420
Grain LNG | Assets and liabilities classified as held for sale    
Disclosure Of Detailed Information About Assets Held For Sale [Line Items]    
Assets held for sale 1,146 1,100
Liabilities held for sale (328) (326)
Net assets / (liabilities) held for sale £ 818 £ 774