The big six energy provider today announced it will increase a typical dual fuel annual energy bill by an average of 9.8% – adding £109 to the cost. This is made up of an average 4.8% increase on gas and 15% on electricity.

Npower said the price rise, the first since October 2013, will impact half of its customers – 1.4 million – with the other 1.4 million not impacted by the changes because they’re on fixed rate tariffs or pre-payment meters.

The price rise will take effect from 16 March and Npower cited the increase in wholesale energy costs and rises in the cost of delivering government policies, such as smart metering and renewables as reasons behind the move.

As part of today’s announcement, the supplier will be launching a four-year fixed term tariff for current standard customers, where the existing penalty will be waived for their “loyalty”.

Simon Stacey, managing director domestic markets at Npower, said: “This is a hugely difficult decision, and we’ve delayed the date this takes effect until after the coldest months of the year.

“Npower operates one of the broadest range of support schemes of any supplier, offering the widest and most diverse care programmes for vulnerable customers and those who are struggling with their energy bills.  We’re already delaying the impact of the increase for vulnerable customers, but anyone who is struggling with their energy bills should contact us straight away to discuss whether they’re on the right tariff for their needs, energy saving help and bespoke payment plans.”

‘A significant dent to customers’ wallets’

Stephen Murray, energy expert at MoneySuperMarket, said: “Coming off the back of EDF’s price increase that starts on 1 March, further price increases from the big six had a certain air of inevitability.

“However, this hefty rise of nearly 10% will add £109 for the average dual fuel customer – a significant dent to customers’ wallets.

“Standard customers continue to pay over the odds for their gas and electricity and whether you’re an Npower customer or with any other supplier on a standard tariff, the message is and has been clear for a while – switch tariff to a cheaper fixed deal and take control of your energy bills.”

See YourMoney.com’s A guide to switching energy provider to see how you could save money on your bills.