Self-Employed Tax Calculator 2026/27: Income Tax, Class 4 and Payments on Account
Sole trader tax on profit with Class 4 National Insurance, the Class 2 treatment, student loan and payments on account — and the split when you are employed as well.
The short answer
Self-employed tax for 2026/27 in one pass: income tax on your profit, Class 4 National Insurance, what happens to Class 2, a student loan if you have one, and whether HMRC will want payments on account — with a salary alongside if you are employed too.
Your Self Assessment bill
Sole trader figures. Ignores capital allowances, losses brought forward and the cash-basis election. Estimate, not advice.
What the self-employed pay in 2026/27
- Income tax on profit (turnover less allowable expenses, or less the £1,000 trading allowance) at 20%, 40% and 45% after the £12,570 personal allowance — Scottish rates for Scottish residents.
- Class 4 National Insurance at 6% on profit between £12,570 and £50,270 and 2% above.
- Class 2 is no longer a charge: from £7,105 of profit it is treated as paid, protecting State Pension and benefit entitlement for nothing. Below that you can pay it voluntarily at £3.65 a week.
- Payments on account: once the Self Assessment bill passes £1,000 (and less than 80% of your tax was collected at source), HMRC asks for half of it again on 31 January and half on 31 July towards the following year — the payments on account calculator lays the dates out.
Employed and self-employed
The salary is taxed first through PAYE and uses up the personal allowance and part of the basic-rate band; the profit is taxed on top at whatever band is left, and Class 4 is charged on the profit separately from the Class 1 already deducted from your pay. The calculator does that split so the figure shown is the extra you owe through Self Assessment.
Landlords are not self-employed
Rental income from an ordinary letting is property income, not a trade: no Class 4, no Class 2, and from April 2026 it goes through Making Tax Digital quarterly updates once gross property plus trading income passes £50,000. Furnished holiday lets lost their trade treatment in April 2025. Use the rental income tax calculator for rent, and this page for a genuine trade.
Sources
The official figures every number on this page is computed from; the site is rebuilt whenever they change.
- HMRC — Rates and thresholds for employers 2026 to 2027 — personal allowance, PAYE bands (England, Wales, Scotland), Class 1 National Insurance thresholds and rates, student loan thresholds; read 12 September 2026
- GOV.UK — Income Tax rates and Personal Allowances — allowance taper above £100,000
- GOV.UK — Repaying your student loan: how much you repay — plan thresholds and 9% / 6% rates
- GOV.UK — Self-employed National Insurance rates — Class 4 6% / 2%, Class 2 treated as paid from £7,105, voluntary £3.65 a week
Quick answers
Income tax on profit after the £12,570 allowance (20%/40%/45%, or Scottish rates) plus Class 4 National Insurance at 6% between £12,570 and £50,270 and 2% above. On £32,000 profit that is about £3,886 income tax and £1,166 Class 4.
Not as a charge. From £7,105 of profit it is treated as paid; below that it is voluntary at £3.65 a week.
Advance payments of half your last bill on 31 January and 31 July, required once the bill exceeds £1,000 unless most of your tax was already collected at source.
Yes, instead of deducting actual expenses — worthwhile only when expenses are under £1,000.
No. Rent is property income with no National Insurance; it is reported on the property pages of the return.