Some small energy companies have begun hiking their prices.
Supplier Toto Energy is raising the price of its variable rate tariffs by up to 27%.
Good Energy has also said it will hike electricity bills on the 18th of January by 7.5% and gas by 6.8% for 70,000 customers.
This means a household with typical usage could see annual dual-fuel bills increase from £1,167 to £1,248.
Toto has also increased the amount it takes in monthly direct debits by 50%.
It says this is to cover extra costs over the colder months between October and March and the amount will drop 50% between April and September.
In a statement, Toto Energy said: “As a small supplier, we do everything we can to minimise cost and pass the savings on to customers.
“But wholesale energy costs have increased this winter and unfortunately, we have to keep up.”