Marriage Allowance allows married couples or those in civil partnerships to share their personal tax allowances. This is the case if one partner earns below the Personal Allowance threshold of £12,570, and the other is a basic rate taxpayer.

It is currently the height of the wedding season, and with new married or civilly partnered lives being forged, there is also the chance to slash taxes.

This is also the case for those who have been married or civilly partnered for many years, so large numbers of Britons may wish to take advantage.

Eligible couples will be able to transfer 10 percent of their tax-free allowance to their partner – worth £1,260 in the current tax year.

Applications can be made at any time, and some will even be eligible for a back payment.

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However, just as a couple can become eligible, they could also fall outside of eligibility due to a circumstantial change.

As a result, couples should always notify HMRC if their circumstances do change.

Marriage Allowance can be claimed online via the Government’s website.

Doing it this way ensures Britons get 100 percent of the money to which they are entitled – without fees.

If an application cannot be made online, then individuals can apply to HMRC in writing, or via their Self Assessment tax return.