As part of the ongoing 'LEAP' (Legal Entitlements and Administrative Practice) correction exercise, latest estimates suggest that as many as 237,000 pensioners have been underpaid, with total owed amounts exceeding £1.46 billion. As of early 2026, the DWP has already identified and paid out over £800 million in arrears to more than 130,000 affected individuals.

Some victims, mostly women, will only be able to claim for 12 months in missed payments. Others will eventually receive all they should have been given but much later than they should have.

The errors dates back to 1985 and centre around the old State Pension scheme where women could claim based on the National Insurance record of a husband, ex-husband or deceased husband.

The National Audit Office released the new figures which came to light after the Department started using a new computerised system to detect victims. Previously checks were done manually, and still victims won't know how much they are owed until their case has been fully reviewed by a specialist at the Department. Some could be owed small amounts, while others could be owed thousands of pounds.

Updated DWP data reveals a more specific breakdown of repayments by category. While the average overall arrears payment is just over £6,000, specific groups have seen widely varying outcomes:

• Married Women: Average repayment of nearly £6,000 (with over 47,000 cases corrected).

• Over 80s: Average repayment of £2,245 (with 34,000 cases corrected).

• Widowed Pensioners: Average repayment of approximately £12,383 (with over 50,000 cases corrected).

Between 2021 and 2025, the Department for Work and Pensions (DWP) undertook a massive, multi-year "correction" exercise known as LEAP, which ultimately identified over 130,000 underpayments - far exceeding the department's initial 2022 estimate of 134,000 pensioners. The majority of those affected were women whose entitlements were miscalculated due to outdated manual systems. At the time of the investigation, the Public Accounts Committee (PAC) issued a scathing report describing the situation as a "shameful shambles."

Dame Meg Hillier, MP and then-chair of the committee, highlighted that the DWP was on its tenth attempt to fix these historical errors since 2018. She described it as "a shameful shambles."

The administrative burden of fixing these mistakes was immense, with staff costs alone originally expected to hit £24.3 million by the end of 2023. However, as the project extended into 2025, the DWP confirmed it had paid out over £800 million in arrears to more than 100,000 widows, married women, and those over 80.

Those most likely to have been underpaid are:

Pensioners who receive low basic State Pension in their own right but are entitled to increase it using their living spouse or civil partner's contributions once they themselves are entitled to the State Pension. Widowed pensioners who are not entitled to a full basic State Pension based on their own contributions but can inherit a basic State Pension from their spouse or civil partner up to the full basic rate. 'Category D' pensioners - men and women receiving low or no State Pension who may be entitled to increase their rate from the age of 80.

The 2026 Focus: Missing HRP Credits

A critical new focus for 2026 is the correction of missing Home Responsibilities Protection (HRP) credits, which primarily affects mothers who claimed Child Benefit before 2000. As of March 2025, this second major exercise had already identified over 12,000 underpayments, paying out an additional £104 million in arrears with an average payout of £8,377. Affected individuals (or their heirs if they have passed away) should use the official HMRC eligibility checker to see if they are entitled to a correction.

Former pensions minister Sir Steve Webb, who is now a partner at pensions specialists LCP, said: "Not only is the cost of the underpayment correction exercise set to soar, DWP are now admitting a whole new category of errors... Far too many people have been underpaid for far too long."

By early 2026, the DWP confirmed that it had completed the vast majority of reviews for the initial three groups (married women, over-80s, and most widows). However, the department has extended its final resolution deadline to the end of March 2027 to ensure all complex and residual cases are fully resolved. If you fall into these groups and have not yet been contacted, you are encouraged to contact the Pension Service proactively to confirm your entitlement.