Self-employed tax calculator 2026/27

The bill, line by line

HMRC builds a self-employed bill in four steps, and the calculator follows the same order. First the profit: turnover less the costs that are wholly for the business, or less the £1,000 trading allowance when that is bigger. Then Income Tax on the profit and any other income, after the Personal Allowance. Then Class 4 National Insurance, which is worked out on the profit alone, never on wages or dividends. Last, any student loan repayment, which HMRC adds to the same Self Assessment statement. The total is due on 31 January after the tax year ends, and from the second year part of the next bill is collected in advance.

The bands that apply to the profit depend on where you live, not where your customers are:

The Personal Allowance shrinks by £1 for every £2 of income over £100,000 and is gone at £125,140. Between those two figures each extra £100 of profit costs 62 % in tax and Class 4 in England, Wales and Northern Ireland, and 69.5 % in Scotland: the £100,000 trap page shows how a pension contribution gets the allowance back.

Why your postcode changes the answer

Most calculators that rank for this search apply the English bands to everyone. Scotland sets its own rates and bands for income from work and business, so the same profit gives two different bills. The gap is small at low profits and grows quickly once the Scottish higher rate starts. The table puts the two side by side for a sole trader with nothing else coming in:

The crossing point is about £33,500 of profit: below it the Scottish starter rate makes Scotland marginally cheaper, above it the intermediate and higher rates take over. Class 4 and student loan thresholds are UK-wide, and dividends are taxed at UK rates wherever you live, which matters when you compare a limited company with staying a sole trader. A full page on Scottish self-employed tax takes the Scottish bands one at a time.

Class 2 has gone; Class 4 has not

Many people still budget for Class 2 because older guides and some calculators still charge it. Nobody has had to pay it since April 2024. If your profit is £7,105 or more, HMRC treats the 2026/27 year as paid for your State Pension record. Below that you can choose to pay £3.65 a week, £190 for the year, to keep a qualifying year. Class 4 remains, at 6 % on profit between £12,570 and £50,270 and 2 % above. The Class 4 calculator and the Class 2 guide go into the detail.

A job and a business at the same time

If you are employed as well, your salary is taxed first through PAYE and uses your Personal Allowance and the lower bands. The profit then sits on top, often entirely in the basic or higher rate, which is why a modest side income can produce a bill out of proportion to it. Class 4 is still charged on the profit alone. With £30,000 of wages and £12,000 of profit, Self Assessment collects £2,400 of Income Tax and £0 of Class 4, so 20 % of the side profit goes to HMRC. The employed and self-employed page has a calculator for exactly that case.

The first January is the expensive one

Payments on account catch out almost every new sole trader. When your Self Assessment bill is £1,000 or more and less than 80 % of your tax was taken at source, HMRC asks for the next year's tax in advance, in two halves on 31 January and 31 July. In the first year nothing has been paid in advance, so the first January carries one and a half years of tax. A sole trader who starts in 2026/27 with £35,000 of profit owes £5,832 for the year: on 31 January 2028 the payment is £8,748, then £2,916 on 31 July 2028. If your profit falls, you can ask HMRC to reduce them. The payments on account calculator handles later years, with the balancing payment.

Making Tax Digital: three thresholds, three dates

Making Tax Digital for Income Tax has been compulsory since 6 April 2026 for the largest sole traders and landlords. It does not change how much tax you pay, only how you report it: digital records kept in compatible software, a summary sent to HMRC every quarter, and the return filed from the same software. Whether you are in depends on qualifying income, which is turnover, not profit:

So a plumber with £55,000 of sales and £25,000 of costs is in from April 2026 even though the profit is only £30,000. The calculator above reads your turnover and tells you which threshold it crosses; the Making Tax Digital checker takes the three years in turn, including rents, and lists your quarterly deadlines.

Sole trader or limited company in 2026/27?

The usual advice, incorporate once profit passes £30,000 to £50,000, dates from years when dividends were taxed at 7.5 % and Corporation Tax was a flat 19 %. In 2026/27 dividends are taxed at 10.75 % and 35.75 %, and Corporation Tax rises from 19 % to 25 % above £50,000. A one-person company that pays everything out as salary and dividends now leaves less cash than a sole trader at most profits in England, Wales and Northern Ireland. What still favours the company is profit left inside it, taxed only at the Corporation Tax rate until you take it out:

That is why the comparison calculator draws the gap as a curve across every level of profit, for everything paid out and for the share you choose to leave in the company, and lets you add the cost of running a company. It does not stop at £50,000.

Putting the right amount aside

1. Open a separate savings account for tax and move a fixed share of every payment you receive into it the day it arrives. The calculator's "put aside" figure is that share.
2. In your first year, add the first payment on account: roughly another half of the year's bill falls due on the same 31 January.
3. Revisit the figure when your profit moves by more than a few thousand pounds, and above all near £50,270, £100,000 and, in Scotland, £43,663, where the rate jumps.
4. Keep records as you go. From the year Making Tax Digital applies to you, your software will show an estimate after each quarterly update.
5. If you pay into a personal pension, the relief changes the bill: try the pension relief calculator.

Every page by profit and by subject

How far to trust the figure

The engine reproduces the worked examples GOV.UK publishes and is tested on every build, and each rate links to the page it was read on. It still makes assumptions: a standard tax code on any wages, an accounting year from 6 April to 5 April, no losses brought forward, no savings interest or capital gains. Your real bill is the one HMRC calculates from your return. The method page lists every rule applied and every rule left out.

This site does better than the first Google result because it gives the whole 2026/27 bill at once, with no email and no profit cap: Scotland included, Class 4, student loans and payments on account, linked to the date Making Tax Digital reaches you, and the sole trader versus limited company gap across every level of profit. Sources read on 15 October 2026.