Becoming a sole trader is the simplest and cheapest way to start trading legally in the UK, and registration itself costs nothing if you do it yourself. The real costs come afterwards, in tax, National Insurance, and the optional extras most sole traders end up paying for once the business is actually running.
This guide covers the genuine 2026 costs of registering and running as a sole trader, what is free, what is optional, and what you are legally required to pay once you start earning.
Registering as a sole trader with HMRC is free if you do it yourself at Gov.uk. Using an accountant or formation service to register for you costs £30 to £100. The ongoing costs are what add up: Income Tax and Class 4 National Insurance on profits above £12,570, optional public liability insurance at £60 to £200 per year, and accountancy fees of £300 to £900 per year if you choose to use one. A realistic first-year budget for admin and compliance alone is £100 to £1,000 depending on how much you do yourself.
Registration Costs
Registering as a sole trader means telling HMRC you are self-employed so you can pay tax correctly through Self Assessment. There is no company to form and no fee to HMRC for doing this directly.
| Registration Route | Cost |
|---|---|
| Register directly at Gov.uk | Free |
| Register via an accountant on your behalf | £30 to £80 |
| Register via a formation/registration service | £40 to £100 |
| Unique Taxpayer Reference (UTR) issue | Free (arrives by post, 10 to 15 working days) |
| Government Gateway account setup | Free |
Doing it yourself takes about 10 minutes online and simply requires your National Insurance number, contact details and a description of your business activity. There is no benefit to paying someone else to do this basic step, though some new sole traders bundle it into a wider accountant engagement for convenience.
When You Must Register
You must register by 5 October following the end of the tax year in which you started trading. The UK tax year runs 6 April to 5 April. So if you started trading in June 2026, that falls in the 2026/27 tax year, and you must register by 5 October 2027.
Registering earlier than the deadline is strongly recommended. Your Unique Taxpayer Reference takes 10 to 15 working days to arrive by post, and you need it well before your first Self Assessment deadline. Leaving registration until close to the 5 October deadline risks missing your first tax return filing window entirely.
Tax and National Insurance
This is where the real cost of being a sole trader sits, not in registration but in ongoing tax obligations on profit.
| Charge | Rate |
|---|---|
| Income Tax, personal allowance | £0 up to £12,570 |
| Income Tax, basic rate | 20% from £12,571 to £50,270 |
| Income Tax, higher rate | 40% from £50,271 to £125,140 |
| Income Tax, additional rate | 45% above £125,140 |
| Class 4 National Insurance | 6% from £12,570 to £50,270, 2% above |
| Class 2 National Insurance (voluntary below small profits threshold) | £3.70 per week if paid voluntarily |
Combined, a basic rate taxpayer sole trader pays roughly 26% of profit above the personal allowance in Income Tax and National Insurance together. This is paid annually through Self Assessment, with payments on account due in January and July once your tax bill exceeds £1,000, which catches many sole traders out in their second year.
Accountancy Costs
An accountant is not a legal requirement for sole traders. Many with simple, single-income finances file their own Self Assessment return using HMRC's free online system at no cost beyond their own time.
| Service | Typical Annual Cost |
|---|---|
| DIY Self Assessment via HMRC online | Free |
| Basic bookkeeping software (FreeAgent, QuickBooks) | £10 to £30 per month |
| Accountant, simple sole trader return | £300 to £600 per year |
| Accountant, more complex finances or multiple income sources | £600 to £900 per year |
| One-off tax return only (no ongoing service) | £150 to £350 |
An accountant becomes genuinely worthwhile once your turnover grows, your finances involve more than one income stream, or the time saved is worth more to you than the fee. Many sole traders start by doing it themselves in year one and switch to an accountant once the business is established.
Insurance Costs
There is no single insurance legally required of every sole trader, but most practical trades need at least one type of cover, and some clients or venues will not work with you without proof of it.
- Public liability insurance: £60 to £200 per year for basic cover up to £1 million or £2 million, more for higher risk trades like construction.
- Professional indemnity insurance: £100 to £400 per year, relevant for consultants, designers, tutors and anyone giving professional advice.
- Tools and equipment insurance: £80 to £250 per year for tradespeople carrying valuable tools.
- Income protection insurance: £15 to £50 per month, optional, covers lost income if you cannot work due to illness or injury.
Other Common Startup Costs
Beyond registration and compliance, most new sole traders budget for a handful of practical extras in their first few months.
- Business bank account: Not legally required for sole traders (you can trade through a personal account), but most banks offer free business accounts for the first 12 to 18 months, then £5 to £15 per month after.
- Business name registration (if trading under a different name): Free, no formal registration needed beyond checking it does not infringe an existing trademark.
- Website and basic branding: £100 to £500 for a simple DIY site, more if commissioning a designer.
- Trade-specific certifications or DBS checks: £30 to £100 depending on trade and requirement.
Sole Trader vs Limited Company
Sole trader status is free and simple, with all profit taxed as personal income and full personal liability for business debts. A limited company costs £12 to register at Companies House, has more admin (annual accounts, Corporation Tax returns), but offers limited liability and can be more tax efficient once profits exceed roughly £40,000 to £50,000 a year, since dividends are taxed differently to salary. Many businesses deliberately start as a sole trader for the free, simple setup, then switch once profits justify the extra admin.
Registering as a sole trader in the UK is free if you do it yourself at Gov.uk, and takes about 10 minutes. The real costs are ongoing: Income Tax and Class 4 National Insurance on profit above £12,570, optional insurance at £60 to £200 a year, and an accountant if you want one at £300 to £900 a year. Register well before the 5 October deadline in the year after you start trading, not right up against it. If you are still deciding on your business structure, see our guide on starting a limited company too.