Registering for self assessment
Registering for Self Assessment refers to the process by which you tell HMRC that you need to send a Self Assessment tax return, if you do not already do so. Once you have registered, HMRC issue you with a unique taxpayer reference (UTR), and send you a formal notice to file a tax return for a year.
If you need to send a Self Assessment tax return for the first time, you will need to register with HMRC for Self Assessment.
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Self Assessment and registration
If you meet certain criteria, HMRC will expect you to register for Self Assessment and complete a tax return. You can read about HMRC’s Self Assessment criteria on our page Who should complete a tax return.
Once you have registered for Self Assessment, HMRC will continue to send you a notice to file a tax return each year until you leave Self Assessment. You do not need to re-register every year.
How to register
There are different ways to register depending on your circumstances. If you are self-employed, see our separate guidance.
If you are not self-employed, you should complete form SA1 to register for Self Assessment. This must either be completed and submitted online through your government gateway account or be completed on screen and then printed off and posted to HMRC. The form is on GOV.UK. If you do not have access to a computer to do this, you should contact HMRC.
When do you need to register
HMRC expect you to register for Self Assessment by 5 October following the end of the tax year that you met the Self Assessment criteria.
You do not need to register if HMRC have already asked you to file a tax return for the year. For example, if you already file Self Assessment tax returns for another reason but you start to receive a new source of income, then you would usually just report that new source of income on the relevant return (though you may need to register separately for class 2 National Insurance if you commence self-employment).
If you have reported a property disposal within 60 days, you may still need to register separately for Self Assessment if you meet the criteria for another reason.
If you already have a unique tax reference (UTR)
If you already have a unique taxpayer reference (often shortened to UTR) – perhaps because you previously filed tax returns but haven’t needed to do so for one year or more – then you should still notify HMRC by 5 October deadline if you need to file a tax return for the previous year.
HMRC will then reinstate your unique taxpayer reference and issue a formal notice to file a tax return for the previous year.
Registering late
The implications of registering late are different depending on whether or not you have a tax liability.
If you owe tax
If you meet the criteria for Self Assessment and owe tax, the 5 October registration deadline is a legal obligation, and you may be charged a failure to notify penalty if you register late. You can read more about the legal requirement to notify on our page How tax is collected.
However, if you notify HMRC after 5 October, then provided you have paid your tax liability in full by the usual 31 January payment deadline the failure to notify penalty should be nil. Paying in full by the 31 January payment deadline will also prevent any late payment penalties being charged.
If you do not owe tax
If you meet HMRC’s Self Assessment criteria, but do not owe any tax, then you do not have the same legal duty to notify by 5 October and HMRC cannot charge you a failure to notify penalty if you register late. However, HMRC say you should register by that date.
