Smaller supplier Tonik Energy has announced an 11% increase in gas and electricity prices.
The company, which supplies around 80,000 customers in the UK, blamed the rise in wholesale energy costs for the increase in its standard variable tariff, Life Energy.
Dual fuel customers will see their bills increase from £979 to £1,085 on average per year, with the price rise coming into effect on 23rd August 2018.
It will affect around 4% or 3,000 of its customers.
The company said it hasn’t increase its tariffs since August 2016.
It added: “However, as a business, it is simply no longer able to continue to do this… Life Energy is still one of the most competitive standard variable tariffs in the market place and is cheaper than any of the Big Six.”
As well as providing 100% of its electricity from renewable sources, the supplier will also provide gas “that contains 10% green gas, with the remainder being carbon offset”.
All the Big Six energy companies have increased tariffs this year, with EDF Energy announcing two price rises..