The price of electricity in Guernsey will rise by 4.8% from September, following the island's regulator approving the hike.
The change was originally supposed to be implemented in April, but was postponed because of the coronavirus pandemic.
The increase will be in place for three years, Guernsey Electricity said.
The company explained the increase was needed to recoup the £7.6m increased cost of importing and generating energy on island between April 2019 and March 2020.
The added costs were "uncontrollable" because of changes in oil prices and exchange rates in the period, Guernsey Electricity added.
Chief executive Alan Bates argued the increase would only lead to an additional £50 a year for an average domestic customer.
He said: "We are mindful of the effect of these large increases and are aware that it is hard for our customers to plan or budget for the increases.
"We are working to find more pragmatic ways to recover costs in future."
BBC News Online
The cost of electricity in Jersey is set to rise by 2.5% from 1 April 2020.
The increase will add about 47p to the average household bill of £972 a year.
Jersey Electricity said the rise had been calculated in line with inflation figures.
Chief executive Chris Ambler added that "prolonged weaknesses" in the value of the pound and its effect on exchange rates with the euro had forced the company to hike prices.
About 95% of Jersey's electricity is imported from France.
"By keeping this rise in line with inflation and by deferring its implementation until after winter, we have tried to minimise the impact on household budgets," Mr Ambler said.
The price of electricity in Jersey has increased by 7% in the last five years, compared to the UK average of 30%, according to Jersey Electricity.Copyright: Getty Images
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