When you make a PAYE, Class 1 National Insurance contributions (NICs) payment for a previous year you'll need to give an adapted form of your PAYE Accounts Office reference number. Your Accounts Office reference is 13 characters long, for example 123PA00045678. You can find this on:
This checker will confirm that the reference is in the right format and gives you the right adapted reference number to use for a given year and ensures your payment goes direct to your account.
Return reference checker start page