Know exactly what you owe HMRC.
Free self-assessment tax calculator for 2025/26 and 2026/27.
No signup. No jargon. Accurate to the penny.
100% Free Calculation
Full tax calculation with band breakdown. No signup needed. Only pay if you want the PDF report.
HMRC 2025/26 Rates
All tax bands, NI thresholds, and allowances verified against current HMRC published rates.
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Whether you're freelancing, renting out property, or driving for Uber.
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Claim every expense you're entitled to. Know exactly how much to save each month.
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Calculate rental profit correctly after mortgage interest, repairs, and insurance.
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Self Assessment Calculator
2025/26
Your exact tax bill. Income tax, NI, expenses, payments on account — everything you need before filing with HMRC.
UK income tax rates. Simplified.
Personal allowance is £12,570 — reduced by £1 for every £2 earned over £100,000. Scotland has separate bands from 19% to 48%.
Basic Rate
20%
£12,571 – £50,270
Higher Rate
40%
£50,271 – £125,140
Additional Rate
45%
Over £125,140
Questions and answers.
What is UK Self Assessment?+
Self Assessment is the system HMRC uses to collect Income Tax from people who need to report income that hasn't been taxed at source. This includes self-employed individuals, landlords, people with dividend or savings income above their allowance, and anyone earning over £100,000.
When is the Self Assessment deadline for 2025/26?+
The online filing deadline for the 2025/26 tax year is 31 January 2027. Paper returns must be filed by 31 October 2026. Late filing attracts an automatic £100 penalty, increasing to £10/day after 3 months late.
Do I need to file a Self Assessment tax return?+
You need to file if you were self-employed with income over £1,000, earned over £100,000 from employment, received untaxed income (e.g. rental, dividends above £500), or HMRC has asked you to file. If in doubt, use HMRC's online tool to check.
What happens if I miss the Self Assessment deadline?+
An automatic £100 penalty applies if you file even one day late. After 3 months, HMRC adds £10/day (up to £900). After 6 months, an additional 5% of tax owed (or £300, whichever is higher). After 12 months, another 5% or £300.
How do payments on account work?+
If your tax bill exceeds £1,000 (after PAYE deductions), HMRC requires advance payments toward next year's bill. Each payment is 50% of your previous year's bill. The first is due 31 January, the second 31 July.