HMRC · 2026
Tax as a self-employed PT — complete guide
The 4 things
What you actually need to do
Most PTs get to year three before someone explains it this simply.
1. Register with HMRC
Once your self-employed earnings cross £1,000 in a tax year (the trading allowance), you have to register. Online, free, takes 10 minutes. You'll get a UTR number in the post — keep it safe.
2. Put 28% aside per payment
Open a second account (Starling/Monzo). Move 28% of every client payment in there the day it arrives. That money doesn't exist for you any more — it's HMRC's.
3. Track every expense
Keep a folder of receipts (or use a £5/mo app like Coconut or 1tap). Every legitimate expense reduces your taxable profit — most new PTs miss £1k–£3k of claimable spend a year.
4. File by 31 January
Self Assessment opens after 6 April and is due 31 January. Filing in May/June is much easier — you still owe in January, but at least you’ll know the number 8 months in advance.
Interactive
Estimate your bill — and what to do next
Enter your numbers below. Set-aside %, VAT proximity and Ltd-vs-sole-trader signals all update live.
Tax Estimator
Quick estimate of your Self-Assessment bill. Updates as you type. Press Esc to clear.
Edit any value — results update live
Enter whole pounds or use a decimal for pence — commas are optional. Currency is GBP (£).
Formatting guide
- Allowed: digits
0–9, commas,, one decimal point., and£. - Decimals: max two places (pence). e.g.
1500.50. - Commas: optional thousands separators — added automatically as you type.
- Not allowed: letters, negative values, multiple decimal points, or values over £10,000,000.
- Empty: blank fields count as £0.
- Taxable profit
- £27,000
- Personal Allowance used(£12,570 tax-free)
- £12,570
- Income tax (20%)
- £2,886
- Class 4 NI (6% / 2%)
- £866
- Class 2 NI(Voluntary from 2024/25)
- £0
- Total estimated tax & NI
- £3,752
- Set aside per month
- £313
This is an estimate only. Speak to an accountant or visit gov.uk for your actual liability.
What this means
Your next steps
Updated live from the figures above — practical actions, not just numbers.
Set aside per £1 earned
14%
≈ £19 per session at 200/yr
Expense ratio
10%
Healthy range for a PT
Distance to VAT
£60,000
Threshold £90,000
Move £313 to a separate account every month
Open a second account (Starling/Monzo) called 'HMRC'. Standing-order the monthly figure on payday — that money no longer exists for you.
Allowable
Expenses PTs can claim (and the ones they can't)
If a cost is wholly and exclusively for the business, it reduces your taxable profit.
✅ Gym rent & venue fees
Floor rent, court hire, studio rev-share (your share of the cost). Keep the invoice.
✅ Insurance & CIMSPA
PI, PL, personal accident, REPS/CIMSPA membership, DBS renewal — all 100% deductible.
✅ Mileage (45p/mile)
First 10,000 business miles per year at 45p. Keep a simple log: date, from, to, miles, client.
✅ Equipment & CPD
Anything under £1,000 in one go is a straight expense. Bigger purchases use the £1m Annual Investment Allowance — still 100% in year one for most PTs.
❌ Everyday clothes
Generic gym leggings and tees aren't claimable — even if you only wear them at work. Branded uniform with a logo printed on IS claimable.
❌ Lunch on a normal workday
Your own food at your usual venue isn't deductible. Meals on a genuine away-day or overnight CPD trip are.
FAQ
Quick answers
When do I need to register with HMRC?
By 5 October following the end of the tax year you started trading. If you started in May 2026 (tax year 2026/27), you must register by 5 October 2027. Earlier is fine — most PTs register the same week they take their first paying client.
When are tax returns and payments due?
Self Assessment is due by 31 January following the tax year (e.g. 2026/27 return due 31 Jan 2028). The same deadline applies to your tax payment. If your bill is over £1,000 you also pay 'payments on account' — half of next year’s estimated bill, due 31 Jan and 31 July.
What expenses can I actually claim?
Anything 'wholly and exclusively' for the business: gym rent, CIMSPA & insurance, equipment under £1,000 in one go, mileage at 45p/mile (first 10,000 miles), phone share, training/CPD, accountancy, music subscriptions used in sessions, and a fair share of home-office bills if you write programmes from home.
How much should I put aside for tax per session?
A safe rule for most early-stage PTs is 28% of every payment into a separate account: roughly 20% Income Tax + 8% Class 4 NICs once you cross the thresholds. Higher earners (over ~£50k profit) should put aside 38–42%.
Do I need an accountant?
Below £30k profit, most PTs file their own Self Assessment in 1–2 hours using HMRC's online portal — it's genuinely straightforward. Above £30k or once you have a Limited Company, an accountant typically saves more than they cost (£300–£600/year is normal).