Are you married or in a civil partnership?
If you’re married or in a civil partnership and one of you has income of less than £11,850 (the Personal Allowance for 2018/19) and the other has income of between £11,851 and £46,350 (the basic rate band for 2018/19), then the higher paid person will be able to claim back up to £238 from the tax man.
If a claim is made, the lower paid party is able to transfer £1,190 of their annual tax free allowance to the higher paid party. That way the higher paid party will have a higher tax free allowance and will therefore pay less tax.
If the same situation existed in previous years you’re able to claim back as far as the 2015/16 tax year. If this is the case you could be owed up to £952.
The person with the lower income has to make the claim and this can be done on HMRC’s website at https://www.gov.uk/apply-marriage-allowance