Research by Uswitch found that some energy suppliers, including EDF and Scottish Power, have already closed applications for their Warm Home Discount schemes.

The price comparison site is urging customers to do their research and apply if they believe they are eligible for the Warm Home Discount or a grant.

Uswitch found that EDF Energy, Scottish Power, Utilita and E have all closed their schemes. EDF says it has reached the maximum number of applications for this year.

Other major suppliers are still open to applications. These include British Gas, E.ON Next, Octopus Energy and Shell Energy. Customers of Bulb, which went into administration in November, can also still apply to its scheme.

The Warm Home Discount aims to reduce fuel poverty by providing low-income households with a £140 discount on their energy bills.

Elderly people on low incomes who receive the Guarantee Credit element of Pension Credit automatically receive the discount. However, people on income support or other allowances have to apply to their participating energy supplier in order to access the money.

Despite some Warm Home Discount schemes now closing, a number of suppliers have grant schemes open to help consumers who are in debt. British Gas, EDF, E.ON, Ovo and Scottish Power all have schemes which can help customers pay off debts, or even buy replacement appliances or repair gas boilers.

Previous Uswitch research found there is a widespread lack of knowledge about the Warm Home Discount Scheme, leading to many eligible households missing out.

Anyone who believes they are eligible should apply as soon as they can, as the scheme is operated on a ‘first come, first served’ basis. There is a fixed pot of money to be distributed, which this year has risen with inflation from £351m to £357m. Qualifying applicants will have their rebates paid by 31 March 2022.

Justina Miltienyte, energy policy expert at Uswitch.com, said: “Eligible consumers have moved swiftly to apply for the Warm Home Discount this year, which means some supplier schemes are already at capacity and closed to further applications.

“If you believe you are eligible for the discount, and your supplier is still accepting applications, we recommend that you apply for it as soon as possible. If your supplier has closed applications but you still need help with your energy bills, you may still fit the criteria under their grant scheme. You should visit their website to see if you are eligible for support.”

If you think you may be eligible for the Warm Home Discount, visit the Pension Credit section of the government website or the Warm Home Discount scheme page for more information.