Tens of thousands of households are entitled to a refund from the Government after missing out on tax credits for disabled children – those affected may be owed up to £4,368 for the current tax year, but you won't be able to backdate refunds.

If you're caring for a child under the age of 16, or a child under 20 currently in eligible education or training, and are in receipt of Disabled Living Allowance (DLA) or Personal Independence Payments (PIP) for that child, then you're eligible for the disability element of child tax credits. The amount you receive will depend on the nature of the child’s disability and the total income of the household.

In last week's Autumn Statement it was announced that between 2011 and 2014, the Department for Work and Pensions (DWP) had failed to share information with HM Revenue and Customs (HMRC) about households in receipt of DLA for children under 16.

This meant that some of these households have not been receiving child tax credits for disabled children that they're entitled to, which equates to an additional £60-£84/week - or £3,120-£4,368/year.

The Government has calculated that around 28,000 households should be able to claim a refund for the 2016/17 tax year and it has set aside £360 million over a five-year period to ensure those refunds are paid.

However, although the ‘data-gap’ occurred between 2011 and 2014, the Government says refunds will only be paid to those affected in 2016/17, as it's claimed that it was up to individuals to check they were in receipt of the right tax credits during previous years.

Check out our Tax Credits guide to see if you're able to claim a payout potentially worth £1,000s.

How do I check if I'm owed money?

If you suspect you’ve not received the appropriate child tax credits then the first thing you should do is ring the HMRC tax credits office to see if staff are aware that you've a child in receipt of disability benefits and that you've received the appropriate sum in child tax credits. You can do this by calling 0345 300 3900.

HMRC has said that claimants should get in touch if they experience a change in circumstances that affects their tax credits claim.

I'm owed money - how and when will I be refunded?

HMRC will contact you directly and automatically adjust your award by the end of January 2017. You'll receive a lump sum payment to reflect entitlement since April 2016, and an ongoing higher award that reflects what you're entitled to.

You'll be reimbursed if you didn't receive the appropriate amount of child tax credits for a disabled child between April 2016 and April 2017. However, any additional child tax credits that were missed before this period will not be retrospectively paid.

According to the policy report released with the Autumn Statement, this is because - while the Government collects data - it is ultimately the responsibility of the individual to ensure that HMRC knows about benefits received.

The report says: “It is the customer’s responsibility to inform HMRC that they receive DLA for their child. It is HMRC’s practice to take data from DWP about such children and update the customer’s CTC awards automatically.”

A HMRC spokesperson said: "HMRC is supporting customers who have not claimed the disabled element of child tax credits by contacting them and automatically updating awards by the end of January.

"Affected customers don’t need to do anything but our advice remains that anyone who becomes eligible for child tax credits should always inform HMRC to receive their full entitlement."