Thousands of grandparents and relatives are missing out on National Insurance (NI) credits worth up to £4,200.

Sir Steve Webb, director of policy at Royal London, says grandparents and other close relatives who provide childcare are eligable to make a claim for the extra cash towards their pension fund.

Mothers with children under 12 are given NI credits to help them maintain their state pension while out of work. Each of the 12 years is equal to £231 of annual pension.

If they return to employment, this pot of credits can instead be claimed by a relative who is acting as childcare.

According to a Freedom of Information request, only about 1,300 people claimed the credits from September 2015 to September 2016.

To qualify for the ‘grandparents’ credit’, relatives need to be of working age and regularly caring for a relative’s child.

Families can also backdate claims up to and including 2011.

“These credits are available to people in a small number of specific circumstances,” said a spokesperson for the Department for Work and Pensions (DWP).

“As with all credits, details of the Specified Adult Childcare credits are well publicised on GOV.UK and are promoted through a number of consumer websites.”

The application form can be found on the government’s website.