Previously if you submitted an error on your payroll to HMRC in an earlier tax year and you noticed the error by 19th April following that tax year, you could amend your payroll records and submit an adjustment (FPS adjustment).
If you noticed the error after 19th April, you would submit an Earlier Year Update (EYU) to HMRC. If your payroll software did not support an EYU submission, you could make the changes through HMRC Basic Tools.
These rules are still applicable for amendments to the 2019/20 tax year and earlier.
From 6th April 2021, errors made in the 2020/21 tax year must be adjusted through an FPS and you no longer submit an EYU. HMRC’s Basic Tools has been updated for this change.
Please see link below for further guidance on correcting payroll mistakes: