People who earned more than £1,000 from self-employment or a side hustle during the 2025/26 tax year are reminded that the deadline to register for Self Assessment for the first time is October 5. The registration is required for those who need to complete a tax return for the first time.
The deadline applies to people who started working for themselves or earning money through a side hustle between April 6, 2025 and April 5, 2026. The £1,000 trading allowance generally means people can have up to £1,000 of gross trading income in a tax year without notifying HMRC, though individual circumstances may differ.
Who needs to register
People whose gross income from self-employment exceeded £1,000 may need to register and file a tax return. However, earning more than £1,000 does not automatically mean tax is due—the amount depends on overall income, allowable expenses, and the individual's tax position.
Self Assessment is the system HMRC uses to collect Income Tax from income not taxed at source. It applies to self-employed people and others with income from freelance work, side hustles, savings, investments, or property.
Allowances and key dates
For the 2025/26 tax year, the Capital Gains Tax annual exempt amount is £3,000, and the Dividend Allowance is £500. The October 5 registration deadline is separate from filing deadlines: paper returns for 2025/26 are due by October 31, 2026, and online returns and payments by January 31, 2027.
Missing the January 31 deadline can result in an initial £100 late-filing penalty, even if no tax is owed, with further penalties if the return remains outstanding.
How to register
First-time registrants can register through the GOV.UK website, providing their National Insurance number and possibly signing in or creating an account. Those unsure whether they need to file can use the Self Assessment checker on GOV.UK.
