Your average monthly trading income before expenses.
Your average monthly business expenses.
Number of months completed in the current tax year (1-12).
Any one-off or irregular income received this year.
Any one-off or irregular expenses incurred this year.
Reg. 07380272 · England & Wales · Est. 2010
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Projected Annual Profit
£38,400.00
Projected Total Tax
£6,895.20
Monthly Net
£2,625.40
Net Income
£31,504.80
Everything you need to know about projecting your self-employed profit
How does the profit projection work?
The calculator takes your average monthly income and expenses over the months elapsed so far, then extrapolates these figures across a full 12-month tax year. It includes any one-off income or expenses you have entered, and calculates projected income tax, Class 2 NI, and Class 4 NI based on HMRC rates for 2025/26. This gives you a realistic estimate of your annual profit, total tax bill, and monthly take-home pay.
What counts as self-employed income?
Self-employed income includes all money received from your trade or profession before expenses. This covers invoiced fees, cash payments, recurring retainers, and any other trading income. You should include the gross amount before any tax or NI deductions. If you receive income from multiple sources (e.g. freelance work and product sales), combine them into your monthly income figure for the most accurate projection.
What expenses can I include?
You can include any allowable business expenses that are incurred wholly and exclusively for your trade. Common examples include office supplies, software subscriptions, professional insurance, travel costs, marketing, accountancy fees, and a proportion of home office costs. Capital expenditure (equipment, vehicles) is handled differently through capital allowances. If in doubt, check HMRC's list of allowable expenses for self-employed individuals.
How accurate is this projection?
The projection is most accurate when your monthly income and expenses are relatively stable. If your business is seasonal or you expect significant changes in the remaining months, the projection may over- or under-estimate your annual figures. You can improve accuracy by updating the calculator each month with your actual figures. The tax calculation uses official HMRC rates and thresholds for 2025/26, but does not account for other income sources or tax reliefs.
When do I need to pay my self-employed tax?
Self-employed individuals in the UK must file a Self Assessment tax return by 31 January following the end of the tax year (which runs 6 April to 5 April). Your tax bill is also due by 31 January. If your bill exceeds £1,000, HMRC may require payments on account — two advance payments on 31 January and 31 July, each equal to half of the previous year's tax bill. Using this projection tool helps you plan ahead and avoid surprises when your tax bill arrives.
Why is profit projection important?
Profit projection is an essential planning tool for self-employed individuals and sole traders. By tracking your actual income and expenses month by month, you can build a reliable forecast of your full-year profit and anticipate your tax liability well before the Self Assessment deadline. This is especially important for managing cash flow and ensuring you set aside enough money to cover your income tax, Class 2 National Insurance, and Class 4 National Insurance contributions.
HMRC-Aligned: This calculator uses official 2025/26 tax rates and thresholds. It provides estimates only — for complex self-employment situations, multiple income sources, or tax relief claims, consult a qualified accountant or tax adviser.
This calculator uses official rates and thresholds from:
Last verified: February 2026 · Tax year 2025/26. Results are indicative — consult a qualified accountant for personalised advice.
Reviewed by M. Samiuddin Quadri, ACCA — Chartered Certified Accountant at Gladstone & Co. · Updated for the 2025/26 tax year.
Disclaimer: This calculator provides estimates based on current HMRC rates and thresholds for the 2025/26 tax year. It does not constitute professional tax, financial, or legal advice. Your actual liability may differ depending on your individual circumstances. Always consult a qualified accountant or tax adviser before making financial decisions. Read our terms