The extension had originally been due to end on 31 July.

The two year extension comes amid signs that HMRC and DWP staff were struggling to deal with the volume of calls on the top up arrangements.

On TV’s Martin Lewis Money Money Show Pensions last night Pensions Minister Laura Trott said that staff had seen a huge rise in the volume of calls about the top up and she wanted no-one to miss out.

Extending the voluntary National Insurance contributions deadline until 2025 means that people have more time to consider whether paying voluntary contributions is the right route for them, a move that could boost their State Pension entitlements.

The original deadline was extended to 31 July 2023 earlier this year, and tens of thousands of people have taken advantage to pay voluntary contributions to HM Revenue and Customs (HMRC) since then, the government said. The revised deadline is expected to enable tens of thousands more to do the same, according to the government.

Victoria Atkins, Financial Secretary to the Treasury, said: “People who have worked hard all their lives deserve to receive their State Pension entitlement, and filling gaps in National Insurance records can make a real difference.

“With the deadline extended, there is no immediate rush for people to complete gaps in their record and they will have more time to spread the cost.”

All relevant voluntary National Insurance contributions payments will be accepted at the rates applicable in 2022 to 2023 until 5 April 2025.

Individuals who are planning for their retirement could benefit from the opportunity to complete gaps in their National Insurance record. Other people who may benefit include those who may have been:

• employed but with low earnings
• unemployed and not claiming benefits
• self-employed who did not pay contributions because of small profits
• living or working outside of the UK

The extension will mean men born after 5 April 1951 or women born after 5 April 1953 have more time to check their records and decide whether to pay voluntary contributions to make up for gaps they may have in their National Insurance record from April 2006. Individuals can usually only pay voluntary National Insurance contributions for the previous six tax years. The deadline is usually 5 April each year.