Self-Employed Tax Calculator
Calculate your Income Tax, Class 2 and Class 4 National Insurance contributions for the 2025/26 tax year. Perfect for sole traders and self-employed professionals.
Instant Calculations
Get immediate tax estimates based on your income and expenses
Potential Savings
See how much you could save with proper tax planning
Professional Guidance
Use our results to make informed tax decisions
Plan Ahead
Better understand your tax obligations for the year
Self-Employment Tax Calculator
Calculate your Income Tax, Class 2 and Class 4 National Insurance contributions for the 2025/26 tax year
Total revenue before expenses
Allowable business expenses
Important Notes:
- Based on 2025/26 tax rates and thresholds
- Class 2 NI: No longer required if profit ≥ £6,845
- Class 4 NI: 6% on profits £12,570-£50,270, then 2%
- Assumes you have no other income or tax reliefs
- For accurate calculations, consult a qualified accountant
Understanding Self-Employment Tax
Income Tax
As a sole trader you pay Income Tax on your taxable profit — turnover minus allowable business expenses. The first £12,570 is covered by your Personal Allowance and is tax-free. Profit between £12,571 and £50,270 is taxed at 20% (basic rate), between £50,271 and £125,140 at 40% (higher rate), and above £125,140 at 45%. Claiming all allowable expenses is the most direct way to reduce your tax bill.
Class 2 and Class 4 NIC
Self-employed individuals pay two types of National Insurance. Class 2 NIC is a flat weekly amount (£3.45 per week in 2025/26) if profits exceed £12,570 — it counts towards your State Pension entitlement. Class 4 NIC is 6% on profits between £12,570 and £50,270, and 2% above that. Unlike employees, you pay no employer NIC — a significant advantage of self-employment over limited company employment.
Allowable Expenses
You can deduct business expenses from your turnover before calculating tax. Common allowable expenses include office costs, travel (excluding commuting), professional subscriptions, accountancy fees, advertising, equipment, and a proportion of home working costs. The more accurate your records, the lower your taxable profit. Cloud accounting software makes tracking expenses straightforward throughout the year — far easier than reconstructing records at self-assessment time.
Making Tax Digital — April 2026
From April 2026, sole traders with turnover above £50,000 must replace their annual self-assessment return with quarterly digital submissions under Making Tax Digital for income tax. If your 2024/25 return shows turnover above £50,000, MTD applies to you from 6 April 2026. The threshold drops to £30,000 from April 2027 and £20,000 from April 2028. Start reviewing compatible software now — HMRC does not provide its own filing tool.
Payments on Account
If your self-assessment tax bill exceeds £1,000, HMRC requires you to make payments on account — advance payments towards next year's tax. Each payment is 50% of the previous year's bill, due on 31 January and 31 July. This catches many sole traders off-guard in their second year of trading. Set aside 25–30% of your profit throughout the year to cover both the current year's bill and the first payment on account due in January.
Related Guides
Essential reading for sole traders and self-employed professionals.
Self Assessment Deadline 2026: Key Dates, Penalties & Tips
The online filing deadline for 2025/26 is 31 January 2027. Miss it and HMRC issues an automatic £100 penalty — even if you owe no tax.
Read guide →Making Tax Digital for Income Tax — What Sole Traders Need to Know
MTD is mandatory for sole traders above £50,000 from April 2026. Here is what changes, what you must do, and the key deadlines.
Read guide →MTD for Income Tax Deadlines and Quarterly Reporting
Under MTD, four quarterly digital updates replace the annual return. Here are the exact deadlines, what to submit, and how to correct errors.
Read guide →MTD for Income Tax — Exemptions, Deferrals, and Who Does Not Need to Join
Not everyone has to join MTD. Here is a full guide to who is exempt, who is deferred, and what action you need to take.
Read guide →Disclaimer: This calculator provides estimates only and should not be considered as professional tax advice. Actual tax calculations may vary based on individual circumstances. For accurate tax planning and filing, consult with our qualified tax professionals.
Book Your Free Consultation
Choose a time that suits you — you'll speak directly with Alex or Shadma, not a chatbot.
You'll receive an instant email confirmation once booked — and a reminder before the call.