iSupplyEnergy has been taken over by Swedish energy firm Vattenfall – but customers have been told they should see "no day-to-day" changes.
The brand will continue to supply gas and electricity to its 120,000 customers, as part of a subsidiary of the Swedish state-owned energy group.
Vattenfall also operates in Denmark, Germany and the Netherlands and has over six million electricity customers and over two million gas customers.
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What does it mean for customers?
A statement on iSupply's website says: "There is no day-to-day impact on our customers – there will be no changes to your account, no interruption to your supply and your payment schedule will remain the same. Our customer call centre will remain in Bournemouth [in the] UK.
It added that the move is "great news" for customers, as the backing and expertise of Vattenfall would allow the company to improve its customer service and products.
If you're on a fixed tariff with iSupply your rate will continue to be fixed for the duration.
Standing charges and unit rates for standard variable tariffs will also remain the same for the time being at least, though if you're on a variable tariff it can always change in future.
iSupply says customers will be notified of any future changes – for more details see its full Q&A.