Income Tax + Class 4 NI · 2025/26
Self-Employed Tax
Calculator 2025/26
Calculate your full self-employed tax bill for 2025/26 — income tax, Class 4 NI and payments on account — so you know exactly what to set aside.
How much tax do self-employed people pay in 2025/26?
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Self-employed sole traders pay income tax at 20% on profits between £12,570 and £50,270, 40% between £50,270 and £125,140, and 45% above £125,140. They also pay Class 4 NI at 6% on profits between £12,570 and £50,270 and 2% above. Class 2 NI was abolished from April 2024.
What are payments on account?
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Payments on account are advance payments towards next year's tax bill. HMRC requires two: 50% of your previous year's tax bill by 31 January and another 50% by 31 July. If your bill is under £1,000 no payments on account are due. This means your January bill is often your tax bill plus the first payment on account for next year — much larger than many people expect.
What expenses can I deduct as self-employed?
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Allowable expenses include: office costs (stationery, phone), travel (but not commuting), work clothing (uniforms, protective gear), staff costs, stock and materials, marketing and advertising, financial charges (bank fees, insurance), business premises, and professional subscriptions. You cannot deduct personal expenses or client entertainment.
When is the self-assessment deadline for 2025/26?
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The online self-assessment deadline for the 2025/26 tax year is 31 January 2027. Paper returns must be filed by 31 October 2026. Any tax owed must also be paid by 31 January 2027. Late filing and payment both incur penalties.
How much should I set aside for tax as a self-employed person?
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A safe rule of thumb is to set aside 25–30% of your profit for tax and NI if you are a basic rate taxpayer, and 40–45% if you earn above £50,270. Put this in a separate savings account as you get paid and you will never be caught short by your tax bill.