Other tax relief deductions 14 - Payments to a trade union
If part of your trade union subscription entitles you to a pension, life assurance or funeral benefits, then you're entitled to tax relief on an amount equal to one half of the part of your union subscription (up to a maximum £100) which provides the benefits. Enter this amount. Your union representative will be able to tell you how much, if any, of your subscription was for these benefits.
If you think the information you are adding has an effect on your 6 April 2020 to 5 April 2021 or 6 April 2021 to 5 April 2022 PAYE Tax codes there is guidance to tell you how to let HMRC know of the change - If you think your code is wrong.