Register for Self Assessment by 5 October

If you started self-employment or letting property and have not filed a tax return before, tell HMRC by 5 October after the end of the tax year (tax years run from 6 April to 5 April).

Deadline

Every year by 5 October

Last checked

Checked against the official source: 21 October 2026

What if you miss the deadline? If you register after 5 October, you could get a penalty for telling HMRC late. Register as soon as you can.

You must send a Self Assessment tax return if, for example, you earn more than £1,000 from self-employment in a tax year. If you have never sent a return, or you did not send one last year, you must register first. The deadline is 5 October after the end of the tax year (tax years run from 6 April to 5 April).

How to do it

1. Use the GOV.UK tool to confirm that you need to send a tax return for the last tax year.
2. Register online on GOV.UK. Sole traders register as self-employed; landlords register for Self Assessment.
3. If you registered in the past but did not send a return last year, reactivate your account instead of registering again.
4. Keep the letter with your Unique Taxpayer Reference (UTR). You need it to file your return.
5. Keep records of your income and expenses from the day you start trading or letting.

Common questions

When do I need to register for Self Assessment?

By 5 October after the end of the tax year in which you needed to file. For example, for income in the tax year that ends on 5 April, register by 5 October of the same year.

Do I need to register if I earn under £1,000 from self-employment?

GOV.UK says you must register as a sole trader if you earn more than £1,000 in a tax year. The first £1,000 is covered by the trading allowance.

Does the deadline move if 5 October is a weekend?

No. HMRC deadlines stay on the same date. Register early to be safe.

Official source: gov.uk (opens in a new tab)

This information is not legal or tax advice.