Married couples could be missing out on £230 per year, according to HM Revenue and Customs (HMRC).

The organisation has revealed that half of couples eligible to claim marriage tax allowance aren't doing so.

Since it was introduced in 2015, only 2.2 million couples have claimed it, from 4.4 million eligible.

Gazette & Herald:

The latest figures were obtained as the result of a Freedom of Information request to HMRC by insurance company Royal London.

Steve Webb, the director of policy at Royal London, said the take-up was "shockingly low".

He said: "When family finances are so tight, I would encourage every married couple to check whether they might be eligible, including for the last two years, as they could qualify for a useful lump sum as well as a reduction in their ongoing tax bill.

"I suspect people don't know who's eligible, or how to go about claiming it."

A spokesman from the HMRC said several advertising campaigns had been running and it to was frustrated by the lack of take-up.

He added: "2.2 million couples across the UK are keeping more of the money they earn thanks to the Marriage Allowance.

"Applications have increased year on year and we have simplified the application process to make it easier for families to apply at a time which is convenient for them."