Doing one thing before April 2025 may help you rack up more than £5,400, Martin Lewis has claimed. In the latest MoneySavingExpert (MSE) newsletter, the financial guru issued a 'six-month' warning about the 'lucrative' opportunity that many Brits simply shouldn't miss.

Remarkably, this is centred around National Insurance and State Pension. He explained:"For each £825 or less you pay to buy National Insurance (NI) years, many gain £5,400+, but much closes in April. It's the MOST LUCRATIVE thing many under age 73 can do, some gain £10,000s. The deadline's half a year away, but the process ain't quick, so start now."

The Government receives NI contributions from employees, employers and self-employed individuals to fund benefits and pensions in the UK. You can view just how much you pay by looking at your payslip, with the amount typically taken before your salary is issued.

Crucially, Martin is encouraging Brits to check their NI record if they're not due to receive a State Pension at this time. As part of this, it's important to look for 'missing full years since 2006' which generally occur if you've taken a career break, spent years abroad or received a low income.

Join the Money Saving Club WhatsApp channel aimed at saving you money and powered by the best content from Reach's national and regional titles

To qualify for a full State Pension, the 52-year-old explained that you'll need to have at least 35 full NI years on record. If you don't, buying them back has the potential to fix this.

This can be achieved through a 2016 HMRC scheme that allows workers to 'buy back years to 2006' rather than 'the usual back six years'. Although the deadline for this was once April 2023, it has since been extended to April 2025. You can do this online or ring HMRC's phone line for assistance.

HMRC also explains: "You have until 5 April 2025 to pay voluntary contributions to make up for gaps between tax years April 2006 and April 2016 if you’re eligible.

"After 5 April 2025 you’ll only be able to pay for voluntary contributions for the past six years. This may not be enough to qualify for a new State Pension if you have fewer than four qualifying years on your National Insurance record. You’ll usually need at least 10 qualifying years in total."

A typical employee NI year costs between £800 and £825, while self-employed years may cost £160, the MSE newsletter added. "Each extra NI year typically adds £329 annually to your State Pension," the gurus continue.

"A 66-year-old man living for the typical life expectancy would get a total of £5,400 back, a woman £6,100."

If you're keen to work this out for yourself, it may be worth checking out MSE's simple State Pension NI contribution top-up calculator.