Letters are being sent out to people who could be affected by an error where Home Responsibilities Protection (HRP) is not added to a person’s National Insurance record.
Mr Lewis said on his BBC podcast this week: “They’ve started to send the letters out. They’re currently going mainly to women who are already of state pension age, that’s those aged over 66. They’ll look at those who are younger later.
“Expect it to be coming in the next few months, so if you haven’t got it yet, don’t panic. My main point is, this isn’t a scam, it could be worth big money, don’t put it in the bin.
“And if you know someone who’s likely to be in that category – it could be your parent – tell them.”
If a person who was owed funds because of the error has died, their next of kin can make a claim on the Government website.
The HRP scheme was put in place to protect parents’ and carers’ entitlement to the state pension with the scheme eventually replaced by National Insurance (NI) credits in 2010.
Tax officials are pouring over NI records to try and identify those entitled to HRP between 1978 and 2010 who don’t appear to have it on their record.
The issue will not affect those who made a HRP claim after May 2000 as the rules changed then so a NI number had to be included on claims.
The DWP previously estimated that 210,000 people have been underpaid a total of £1.3billion in state pension owing to historical issues with their HRP.
But officials are unsure what the true figure is and it could range from £310million to upwards of £1.5billion.
In one success story, a 74-year-old woman from Cornwall received almost £17,000 in back payments and her state pension was increased by £30 a week.
She was missing NI credits for several years between 1978 and 1988. Prior to being uprated, her state pension was just £134 a week, with the full basic state pension currently at £156.20 a week.
State pension payments are set to increase 8.5 percent next April in line with the triple lock, as the rise in average earnings metric is now set to determine the percentage increase.
The Martin Lewis podcast is available on BBC Sounds.
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