v3.25.3
Exceptional items and remeasurements - Schedule of exceptional items and remeasurements from continuing operations (Details) - GBP (£)
£ in Millions
 6 Months Ended
Sep. 30, 2025
Sep. 30, 2024
Included within operating profit from continuing operations    
Operating profit £ 1,526 £ 1,309
Included within net finance costs    
Net gains on financial assets at fair value through profit and loss 2 3
Net finance costs (739) (682)
Included within share of post-tax results of joint ventures and associates    
Share of post-tax results of joint ventures and associates 39 57
Profit before tax 826 684
Tax on exceptional items and remeasurements (208) (112)
Profit after tax from continuing operations 618 572
Exceptional items and remeasurements    
Included within operating profit from continuing operations    
Provision for UK electricity balancing costs   151
Major transformation programme (15) (42)
Transaction, separation and integration costs (19)  
Changes in environmental provisions 25 (1)
Net gains on commodity contract derivatives 16 (9)
Operating profit (89) 99
Included within net finance costs    
Net (losses) gains on derivative financial instruments (63) (15)
Net gains on financial assets at fair value through profit and loss 2 3
Net finance costs (61) (12)
Included within share of post-tax results of joint ventures and associates    
Net (losses) gains on financial instruments   (3)
Share of post-tax results of joint ventures and associates 0 (3)
Profit before tax (150) 84
Tax on exceptional items and remeasurements 15 17
Profit after tax from continuing operations (135) 101
Exceptional items and remeasurements | National Grid Renewables    
Included within operating profit from continuing operations    
Net loss on disposal of NG Renewables (96)  
Exceptional items    
Included within operating profit from continuing operations    
Provision for UK electricity balancing costs   151
Major transformation programme (15) (42)
Transaction, separation and integration costs (19)  
Changes in environmental provisions 25 (1)
Net gains on commodity contract derivatives 0 0
Operating profit (105) 108
Included within net finance costs    
Net (losses) gains on derivative financial instruments 0 0
Net gains on financial assets at fair value through profit and loss 0 0
Net finance costs 0 0
Included within share of post-tax results of joint ventures and associates    
Net (losses) gains on financial instruments   0
Share of post-tax results of joint ventures and associates   0
Profit before tax (105) 108
Tax on exceptional items and remeasurements 2 11
Profit after tax from continuing operations (103) 119
Exceptional items | National Grid Renewables    
Included within operating profit from continuing operations    
Net loss on disposal of NG Renewables (96)  
Remeasurements    
Included within operating profit from continuing operations    
Provision for UK electricity balancing costs   0
Major transformation programme 0 0
Transaction, separation and integration costs 0  
Changes in environmental provisions 0 0
Net gains on commodity contract derivatives 16 (9)
Operating profit 16 (9)
Included within net finance costs    
Net (losses) gains on derivative financial instruments (63) (15)
Net gains on financial assets at fair value through profit and loss 2 3
Net finance costs (61) (12)
Included within share of post-tax results of joint ventures and associates    
Net (losses) gains on financial instruments   (3)
Share of post-tax results of joint ventures and associates   (3)
Profit before tax (45) (24)
Tax on exceptional items and remeasurements 13 6
Profit after tax from continuing operations (32) £ (18)
Remeasurements | National Grid Renewables    
Included within operating profit from continuing operations    
Net loss on disposal of NG Renewables £ 0