THOUSANDS of pensioners could be owed over £6,900 in back-payments - here's how to check if you're due one.
The Department for Work and Pensions (DWP) has admitted to mistakes that has led to some women not being paid extra state pension payments.
Women who hit state pension age before April 2016 should check if they're due a payout.
Widows, divorcees and women who rely on their husband's pension contributions for some of their pension entitlement are mainly affected.
Women over 80 - regardless of whether they're married or not - should also look to see if they're owed cash.
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Latest figures show that £209million in state pension underpayments is owed back - equating to £6,958 per case.
But the amount you are due could be lower, or even higher than that - one divorced woman won back a £60,000 lump sum after missing out on the money for years.
Pensioners affected should have received increases to the basic state pension.
But they didn't due to an error that the National Audit Office has blamed on complex rules and outdated IT systems that require claims to be made manually instead of being automated.
Estimates show that retirees were underpaid £1billion in total because of the blunder.
The DWP said it expects to make repayments by the end of this year - here's how to check if you're due one.
Who is affected by state pension underpayments?
Retired stay-at-home mums may have missed out on a pension hike when their husbands retired.
The injustice only affects wives who retired before 2016. After this date, women’s pensions were no longer linked to their husbands.
Their payments should have risen to 60% of their husband’s basic state pension, the amount women with low national insurance contributions got under the old pension system.
In the previous tax year when the issue was first uncovered, they would get £80.45 a week, 60% of their husband’s £134.25 a week.
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Instead, they are getting more like £67 a week.
How much you’ll get in compensation depends on when your husband retired.
If it was between April 2008 and 2016, you’ll get all your losses back as the Government should have increased your pension automatically.
Those whose husbands retired before 2008 had to apply for the extra cash, although in many cases they lost out because they didn’t know about it.
Women in this position can only get a year of backdated payments.
This online tool was launched by former pensions minister Steve Webb on behalf of actuarial firm LCP, after he first uncovered cases of women being paid the wrong state pension via his This Is Money column.
If you use the LCP calculator and think you're eligible for a top-up in either scenario, then the DWP should pick up the error in their own records too.
How do I claim a payout?
You don't need to do anything.
If you are owed money, you'll likely have to sit tight and wait for the DWP to send you a letter confirming your payment.
Those considered at "high risk" like those over 80 and widows are being prioritised.
Pensioners can't go directly to the DWP and query whether they have been affected.
However, you can call the Pension Service for more information if you think you are affected.