ScottishPower said today that its UK customer numbers have fallen by 100,000 since the end of last year to five million.
The figures come less than a week after it announced plans to increase its standard variable gas and electricity prices by 5.5% from June 1, impacting 950,000 households.
ScottishPower said the “Beast from the East” cold snap in February and March helped drive higher earnings as it boosted demand for gas in the first quarter.
Keith Anderson, chief executive at ScottishPower, said: “The improvement in generation and supply follows a very difficult 2017, which delivered one of the weakest performances for the business in the last decade.
“The first three months of the year has seen the business recover to a level just below the first quarter in 2016.
“With the price cap pending this year, we still expect a challenging environment for the retail business in 2018.”