Side hustle or selling online: do you need to tell HMRC?

The short version

If your gross trading income in a tax year is £1,000 or less, you generally do not need to tell HMRC. If it is over £1,000, you must register for Self Assessment. Online platforms also report sellers to HMRC each year, and being reported does not automatically mean you owe tax.

The trading allowance

The trading allowance is up to £1,000 a year. It is measured on your gross trading income: the total before any expenses are taken off.

If your income is £1,000 or less

If your gross trading income in a tax year is £1,000 or less, you generally do not need to tell HMRC. There are exceptions, for example if you have to send a tax return for another reason.

If your income is over £1,000

You must register for Self Assessment. If you are self-employed, the deadline is 5 October after the end of the tax year you earned it in. The tax year runs from 6 April to 5 April. For example, income earned between 6 April 2026 and 5 April 2027 means registering by 5 October 2027. Registering late can lead to a penalty.

Is it trading?

Selling now and then is not always trading. Regular sales made for profit are a sign of trading. If you are not sure, HMRC says to contact them.

What online platforms tell HMRC

Online platforms report sellers’ details and income to HMRC each year, by the following January. A seller is not reported if they make fewer than 30 sales of goods in a calendar year and receive less than 2,000 euros (about £1,700) for them. Being reported does not automatically mean you owe tax.

About this guide

Tax year: 2026/27 (6 April 2026 to 5 April 2027).

Last checked: 12 October 2026 against GOV.UK.

GOV.UK pages used:

• Tax-free allowances on property and trading income
• Register for Self Assessment
• Selling goods or services on a digital platform
• Working for yourself

This guide is general information, not tax advice.