The time limit on claiming higher rate tax relief on pension allowances is set to be cut from six to four years from 6 April, Standard Life warns.
The life and pensions firm says many members of group personal pensions - including employers backed GPPs and stakeholders - are only taking advantage of half of the tax relief they are due.
There are nearly 3m higher rate taxpayers in the UK and Standard Life estimated a quarter of a million people do not claim higher rate tax relief.
The firm says such schemes automatically give individuals basic rate tax relief, but it is up to them to reclaim higher rate relief if they are eligible. However, for the many people who don't complete a self-assessment this requires action on their part.
Standard Life senior pensions policy manager Andrew Tully says some people miss out through apathy, or because they don't know the onus falls on them.
People are able to claim backdated tax relief, however, the government is reducing the time limit for making these claims from nearly six years to four years from April 6.
Tully explains: "It's no secret that higher rate tax relief is an exceptionally valuable benefit but, despite that, many people are not aware they need to ask for this extra relief.
"Claiming your tax is straightforward as you simply have to write to your local tax office.
"But the clock is ticking, so taking action now could save you money. Given the current financial climate, a cheque from the revenue will come as a welcome bonus."
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