Self Assessment Tax Return Calculator UK
UK Self-Employed Tax Estimate Calculator
Estimate Income Tax, Class 4 National Insurance, voluntary Class 2 and payments on account for England, Wales and Northern Ireland.
Net self-employed profit
Income Tax
Class 4 NIC
Total due before tax paid
| Total taxable income | £0.00 |
| Personal Allowance used | £0.00 |
| Voluntary Class 2 NIC | £0.00 |
| Tax already paid | £0.00 |
| Balancing payment due | £0.00 |
| Payments on account total | £0.00 |
| Estimated amount to set aside | £0.00 |
This is an estimate only. It does not cover Scottish income tax, student loans, Marriage Allowance, dividends, capital gains or special reliefs.
UK Self-Employed Self Assessment Calculator
England, Wales and Northern Ireland. This calculator uses Self Assessment style inputs and explains what each figure means in plain English.
How to use this calculator: enter the figures from your records for the tax year. If a box does not apply to you, leave it as 0.
This is most useful for sole traders and self-employed people who want help understanding the figures before completing a tax return.
Tip: if you are unsure about a field, read the helper text under it before entering a number.
Net business profit
Income Tax
Class 4 NIC
Balancing payment
| Total income included | £0.00 |
| Adjusted net income | £0.00 |
| Personal Allowance used | £0.00 |
| Taxable income | £0.00 |
| Voluntary Class 2 | £0.00 |
| Student loan | £0.00 |
| Postgraduate loan | £0.00 |
| Total before tax already paid | £0.00 |
| Total tax already paid / deducted | £0.00 |
| Payments on account total | £0.00 |
| Estimated total to set aside | £0.00 |
This is an estimate for straightforward cases. It now supports tax codes 1257L, BR, D0 and 0T, plus common employee NIC categories. It does not cover every payroll situation, cumulative PAYE adjustments, Scottish tax, benefits in kind, attachment orders, student loans or employer pension contributions.