Starting a side hustle in the UK: a checklist
The first month decides whether the admin stays easy. Tick off what you have set up, in the order that saves the most trouble later.
Starting a side hustle in the UK: a checklist
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Start the record on day one
A date, an amount and who paid is enough. A hustle that starts with a spreadsheet works, and the moment it stops working is the moment you need something better.
The £1,000 line comes first
Under £1,000 of gross trading income in the tax year you generally do not need to tell HMRC. Over it you register by 5 October after the tax year ends, so it helps to know early.
Know the real rate
What you charge and what you earn an hour after costs are different numbers. The second one is the one that tells you whether to keep going.
Figures for the 2026/27 tax year, checked 25 October 2026. Sources: Tax-free allowances on property and trading income; Invoices: what they must include. An estimate, not advice. SideTill is not tax software.
Keep the number for every month
SideTill is the simple record of your side hustle: log the job, send the invoice, record the money when it comes in, and see whether the month actually made you money. It also shows your best month, so you can tell a bad month from a bad habit.
Get SideTill
No account. No sign-up. Your data stays on your phone. The basics are free to use.
Questions
Do I need a business bank account?
Not to start. Keeping business money easy to find helps, whether that is a separate account or a clear record.
Do I need insurance?
That depends on the work. Check with an insurer for anything where a client or a third party could be harmed.
Is this tax advice?
No. It is a checklist from gov.uk's published guidance. For your own situation ask HMRC or an accountant.