British Gas owner Centrica said today that it lost more than 200,000 customers in the first three months of the year as competition in the energy market continued to bite.

The country’s largest gas and electricity supplier said in a first-quarter trading update that it suffered a net loss of around 224,000 residential customers – or 1.5% of home supply – in the period, with its overall residential accounts totalling falling to 14.4million.

Centrica attributed the loss to significant number of customers coming off long-term fixed-price contracts and switching suppliers as smaller rivals put the “Big Six” players under price pressure.

The UK energy industry has a total of 39 suppliers, although the Big Six – British Gas, SSE, npower, ScottishPower, EDF and E.ON – still account for 85% of all energy accounts.

Centrica added that it axed 800 jobs during the first quarter, less than a third of the 3,000 roles it intends to cut this year as part of its plans to save of £750m over five years.

The group announced last July that it would cut 6,000 posts over five years, around 10% of its workforce, although 2,000 jobs will be created, resulting in a net loss of 4,000 over the period. This year’s savings are expected to reach £200,000.

Chief executive Iain Conn said: “We continue to make good progress in implementing our strategy and, with improving levels of customer service, good operational performance, lower costs, and the launch of new products to help customers manage their energy usage, we remain on track to deliver against our 2016 targets.”

British Gas has cut prices three times since the beginning of 2015, and in January it lowered gas tariffs in line with other Big Six providers, announcing a 5.1% decrease from March 16.

However, consumer groups argue that gas prices in wholesale markets have fallen by some 40% since 2014, while electricity prices have dropped by around 30%.

Ann Robinson, director of consumer policy at uSwitch.com, said: “British Gas has made more price reductions since the start of 2015 than any of the Big Six, but it should go further.”

Centrica also came under attack over its plans for job cuts.

Brian Strutton, national officer at the GMB union, said: “Staff are confused and disillusioned, managers don’t know if they’re staying or going and the only word from the top is cut, cut, cut.

“Announcing even more job losses will be a bitter blow and GMB will be consulting with shop stewards and reps to discuss what steps to take,” he added.