LONDON (Reuters) - Centrica (L:CNA), Britain's largest energy supplier, lost 399,000 customers in the first half of the year, contributing to a 13 percent dip in revenue, the company said on Thursday.
Britons have grown increasingly dissatisfied with high bills and poor customer service, leading to a rise in the number of people switching suppliers.
Centrica said the drop in customers was partly due to a number of people coming to the end of fixed-term contracts, adding it returned to account growth in June following the launch of new contracts.
"We will continue our focus on developing innovative products, differentiating our offer and giving our residential and business customers more choice," the company said in a statement.
Centrica, which owns British Gas, said this month it would offer free electricity on either Saturdays or Sundays to its British Gas customers who have installed smart meters.
Revenue fell 13 percent to 13.38 billion pounds ($17.64 billion) in the first half of 2016, compared with the same period last year, with adjusted operating profit down 12 percent at 853 million pounds.
Centrica said the impact of Britain's decision last month to leave the European Union would have a limited short-term impact on the company though consumer confidence, interest rates and foreign exchange.
"Our focus is on understanding what the result means for energy and other business regulations over time and how the changed involvement of the UK would impact the competitiveness of the European energy markets," it said.