Tax and money
A simple guide to Self Assessment for the self-employed
Updated 21 September 2026 · 6 min read
For a lot of sole traders, Self Assessment is the most stressful part of the year, and almost all of that stress comes from leaving it until January with a shoebox of receipts. It is far more manageable than it looks once you know the shape of it. Here is the plain-English version of what you need to do and when.
This is general guidance, not tax advice. Rules and figures change, so check gov.uk or speak to an accountant about your own situation.
Do you need to file?
If your income from self-employment in a tax year is more than the trading allowance of one thousand pounds, you generally need to register with HMRC and complete a Self Assessment tax return. Below that, the trading allowance usually means you do not have to. If you are not sure, gov.uk has a short checker that will tell you.
The dates that matter
The UK tax year runs to 5 April. If you have started working for yourself, register for Self Assessment by 5 October after the end of the tax year in which you started. The main deadline to file your return online and pay what you owe is 31 January after the tax year ends. Some people also make payments on account towards the next year, due 31 January and 31 July.
- Tax year ends 5 April
- Register by 5 October after the year you started
- File online and pay by 31 January
- Payments on account, if they apply, are due 31 January and 31 July
What you can claim
You pay tax on your profit, not your turnover, so allowable business expenses reduce what you owe. Depending on your trade that can include materials, stock, tools, business travel and mileage, a proportion of your phone and home use, and more. The rule of thumb is that a cost has to be genuinely for the business. Keep the receipts and a record of each one.
Keep the records as you go
The single thing that makes Self Assessment painless is keeping your income and expenses tidy through the year instead of reconstructing them in January. Log what comes in and what you spend as it happens, keep the receipts, and by the time the deadline comes round the numbers are simply there. It turns a dreaded weekend into a quick job.
The short version
- Over the one thousand pound trading allowance, you generally register and file
- Key dates: tax year ends 5 April, file and pay by 31 January
- You are taxed on profit, so allowable expenses reduce the bill
- Keeping records through the year is what makes January easy
Soopaspace keeps your income from bookings and your expenses tidy through the year, lined up the way Self Assessment asks, so filing is quick to do yourself or hand to an accountant.
See how Soopaspace keeps your books readyCommon questions
- What is the trading allowance?
- It is a one thousand pound allowance for casual or self-employed income. If your self-employed income for the year is under it, you generally do not need to report it; over it, you usually register for Self Assessment.
- What records do I need to keep?
- A record of your income and your business expenses, with receipts, kept for the period HMRC requires. Keeping them as you go, rather than at year end, is the whole game.