Tax
Estimate standard 2026/27 Income Tax and Class 4 NI from modeled trading profit.
Calculator currency
This rule-sensitive calculator is fixed to GBP (UK 2026/27) for England, Wales and Northern Ireland.
FinTrex result
UK Self-Employed Tax Estimate
Estimated Income Tax + Class 4 NI
£13,889
Modeled trading profit
£60,000
Modeled profit after these deductions
£46,111
What changes this most?
Business profit, not revenue, is the starting point in this simplified model. Expense classification matters.
Sensitivity check
A roughly 10% move in annual self-employed revenue changes the modeled headline result by up to £3,360 in this setup.
Educational 2026/27 estimate. Self-employed tax can involve other income, allowances, VAT, losses and payments on account.
Use the number fields, sliders, or a quick preset. You can fully clear a field while editing.
Formula
Taxable trading profit is gross revenue less entered deductible expenses; standard 2026/27 Income Tax and Class 4 National Insurance are then estimated.
Rule context
Reviewed against: GOV.UK 2026/27 Income Tax and National Insurance rates (verified 21 Aug 2026)
Adjust one assumption at a time to understand which inputs have the greatest effect. Compare several realistic scenarios rather than relying on a single projection.
Default assumptions are maintained by FinTrex and may not reflect current products or rates available to you. Review every input before using the estimate.
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