Npower said that it will cut standard annual gas bills by an average of 5.2 per cent from March 28th. This will make its average annual standard domestic gas tariff £32 cheaper at £591 per year. It added that the move will help 1.2m of its customers.
Paul Coffey, chief executive of Npower, said: "This cut in gas prices is welcome news for many of our customers."
"We have balanced the wholesale price fall against increases in the other costs we are charged."
It comes as energy prices are plumbing historic lows, with US oil prices crashing below $27 per barrel for the first time in 2003 earlier this year.
Consumer groups have heaped pressure on energy firms to adequately pass on record low wholesale gas prices to their customers. Analysis by market information provider CIS found wholesale gas and electricity prices in the UK hit a five-year low at the end of 2015.