If you’re self-employed as a nail tech, self-assessment is part of life. But for many people, it’s also one of the most stressful parts of running their business. Missed deadlines, unexpected tax bills, confusion over what to include. Sound familiar?
This guide breaks it all down in plain English.
What Is Self-Assessment and Who Needs to Do It?
Self-assessment is how HMRC collects Income Tax from people who aren’t on PAYE. As a self-employed nail technician, you need to complete a self-assessment tax return each year to declare your income and expenses, and pay any tax owed.
You’ll need to register if:
- You earned more than £1,000 from self-employment in a tax year
- You have other untaxed income (such as rental income or savings interest above your allowance)
- HMRC writes to you asking you to file a return
The tax year runs from 6 April to 5 April. So for the 2025/26 tax year, you’ll be filing a return covering income from 6 April 2025 to 5 April 2026.
Key Dates to Know
These are the deadlines you absolutely cannot miss:
- 5 October: Register for self-assessment if it’s your first time
- 31 October: Paper return deadline (if you’re filing by post)
- 31 January: Online return deadline and payment of any tax owed
- 31 July: Payment on account deadline (if applicable)
Miss the 31 January deadline and you’ll face an automatic £100 fine, with further penalties the longer you leave it. HMRC’s guidance on self-assessment penalties sets out the full details.
What Do You Need to Include in Your Return?
Your self-assessment return needs to capture all your income for the year, not just your nail tech work. That includes:
- Income from clients (cash, bank transfer, card payments)
- Tips received
- Income from any other self-employed work
- Employment income if you also have a PAYE job
- Any other untaxed income
Business Expenses
You can deduct allowable business expenses from your income before calculating tax. For nail technicians, this typically includes products, equipment, chair rental, training, marketing, and professional fees including accountancy. We cover this in detail in our guide to what nail technicians can claim as expenses.
What Is the Trading Allowance?
If your gross self-employment income is £1,000 or less, you may be able to claim the trading allowance instead of deducting actual expenses. This means you don’t need to keep detailed expense records for very small amounts of income.
However, if your income exceeds £1,000 (which is likely if nail tech is your main work), you’ll want to track and claim your actual expenses properly. This almost always results in a lower tax bill than the trading allowance.
Payments on Account: What Are They?
Once your self-assessment tax bill exceeds £1,000, HMRC asks you to make advance payments towards the following year’s tax bill. These are called payments on account, and they’re paid in two instalments:
- 50% by 31 January
- 50% by 31 July
This catches many nail techs off guard in their second year of trading, when they suddenly face a larger-than-expected January payment. Planning ahead for this is one of the key things a good accountant will help you with.
Common Mistakes Nail Technicians Make on Self-Assessment
- Forgetting to include cash or Revolut/PayPal payments from clients
- Missing the October registration deadline in year one
- Not claiming all allowable expenses (especially home use, training, and tools)
- Confusing turnover with profit when estimating what tax is owed
- Leaving it to the last minute and rushing the return
How Simplr Can Help
At Simplr Accounting, we handle self-assessment returns for nail technicians and other self-employed beauty professionals. We’ll make sure your return is accurate, submitted on time, and that you’re only paying the tax you actually owe.
We work entirely online, using cloud accounting software that connects to your bank and tracks income and expenses automatically. No spreadsheets, no shoeboxes of receipts.
Find out more on our nail technicians page or explore our full range of services at simplraccounting.co.uk/services.
Book a Free Discovery Call
If self-assessment feels overwhelming, you don’t have to work it out alone. Book a free, no-obligation call with us and we’ll walk you through exactly what you need to do. No jargon, no pressure.