Guides for sole traders
Short, plain guides to the self assessment questions that come up every winter. Every figure comes from GOV.UK and links to the source.
Self assessment deadlines 2027
File and pay by 31 January 2027 for 2025/26. What late filing and late payment cost, and the 7.75% interest rate.
Read the guidePayments on account explained
Why your first January bill can be 1.5 times your tax. The £1,000 and 80% rules, with a worked example.
Read the guideSelf-employed tax rates 2026/27
Income tax for England, Wales, Northern Ireland and Scotland, Class 4 and Class 2, and the £100,000 taper. With 2025/26 alongside.
Read the guideHow much to save for tax
Set-aside percentages for £20,000 to £80,000 of profit, worked out from the real rates, with the sums shown.
Read the guideMaking Tax Digital for Income Tax
Over £30,000 from April 2027 and £20,000 from April 2028. Why it is based on turnover, and the quarterly deadlines.
Read the guideSimplified expenses
55p a mile for 2026/27 (45p before), use-of-home flat rates and the £1,000 trading allowance.
Read the guide
Rather just see your number?
Sole Sums works out your 31 January and 31 July payments for 2025/26 and 2026/27. Free, no account.
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