The company, which is the last of the big six suppliers to reveal its price cuts after the change in policy, will now partially roll back the 10.4 per cent price increase that took effect from 1 December.
Npower will cut £38 from bills on 28 February and pass on the £12 government rebate in the Autumn.
“This reduction is a reflection of the recent review of two government policies and their impact on household energy bills and it is a welcome start,” said Paul Massara, chief executive of parent company RWE Npower.
Peers British Gas and SSE have both said they would pass on the full savings from the green levy cutback. But customers on fixed tariffs at other big six firms such as Scottish Power are unlikely to see their bills reduced. Consumer group uSwitch said that consumers are still £53 per year worse off on average after the latest cuts.