Boost Power, a subsidiary of Ovo Energy that supplies gas and electricity to 200,000 prepayment customers, is to close later this year.
Customers will be moved over to Ovo Energy automatically, with letters already being sent out to households.
If you’re being switched over, you won’t need to do anything and there will be no disruption to your energy supply.
Some customers have been told their account will be moved over from May 20, according to The Sun.
Boost was launched by Ovo Energy in 2017 as an offshoot for its prepayment meter customers.
Customers on prepayment meters need to top up using a key, card or app to keep the energy supply in their home.
An OVO Energy spokesperson told The Mirror: “We’re ready to welcome our Boost customers to OVO Energy where they will receive new, green benefits - all free or at a discounted price.
“As part of our new Path to Zero offering, customers can receive energy insights, advice on how to reduce unnecessary energy usage, upgrade or improve their boiler, and use energy efficient technology.”
The news of Boost closing comes after hundreds of its customers were hit with unexpected bills after the gas and electricity firm accidentally undercharged them.
The issue happened after defective smart meters gave lower energy readings by mistake.
An email seen by The Mail on Sunday reads: “Unfortunately, when our prices went up in October, your meter wasn't updated due to a technical problem.
“This means we were charging you less than we should have for a short period of time. We're sorry about this.”
It continues: “What happens next: you will need to pay back the difference.”
The newspaper claims some households have been given additional bills of up to £700.
Boost is offering some customers a discount of 10% and said those who are deemed the most financially vulnerable won’t have to pay the money back.
A spokesman said: “A small number of customers were paying too little for a short period due to a technical issue.
“We're here to help any customers who would like additional support with an affordable plan.”
The Mail on Sunday claims Ofgem is now investigating the incident.
Octopus Energy accidentally charged customers just 0.1% of the amount of gas they used during winter - but households didn't have to pay the money back.
