When you make your Self Assessment payment you will need your Self Assessment reference number, also referred to as your unique taxpayer reference (UTR). You'll find this on your:
The reference number is made up of 11 characters, for example: 1234567890K.
This checker only tells you that the reference is in the right format to allow your payment to go direct to your account.
To check that your reference number is in the right format, please enter it in the box below then click on the 'Check reference' button.
When you make your payment please enter the reference number in exactly the same format as shown, with no spaces. If you do not, your payment will take longer to go to your account.