The UK energy supplier is the fifth big six provider to hike prices in 2018.
Last week, npower announced that it would increase prices by 5.3% — or £64 per year — on average for gas and electricity customers on dual fuel, variable rate tariffs. Those on gas-only tariffs will see a 4.4% increase; those on electricity-only tariffs will see a 6.2% hike.
These rate increases takes effect 17 June 2018, at which time npower will have the most expensive big six standard energy tariff.