v3.26.1
Finance income and costs (Details) - GBP (£)
£ in Millions
 12 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Mar. 31, 2024
Finance income      
Net interest income on pensions and other post-retirement benefit obligations £ 114 £ 98 £ 100
Interest income on financial instruments:      
Bank deposits and other financial assets 263 341 139
Dividends received on equities held at fair value through other comprehensive income (FVOCI) 0 1 1
Net gains on FVTPL financial assets 2 1 4
Other income 1 9 4
Finance income 380 450 248
Interest expense on financial liabilities held at amortised cost:      
Bank loans and overdrafts (115) (110) (140)
Other borrowings (1,591) (1,553) (1,424)
Interest on derivatives (229) (285) (277)
Unwinding of discount on provisions and other payables (123) (130) (102)
Other interest (15) (26) (31)
Derivatives designated as hedges for hedge accounting (24) 4 13
Derivatives not designated as hedges for hedge accounting (32) (1) (2)
Less: interest capitalised 424 294 251
Finance costs (1,705) (1,807) (1,712)
Finance income and costs (1,325) (1,357) (1,464)
Net foreign exchange gain (loss) on financing activities £ (711) £ 241 £ 271
Capitalisation rate of borrowing costs eligible for capitalisation 4.40% 4.30% 4.70%
Tax relief on capitalised interest £ 65 £ 39 £ 39
Amount of accretion on inflation linked liabilities £ 168 £ 152 £ 208