Calculators for the self-employed.
Quick estimates of your tax bill, your CIS refund and whether the VAT Flat Rate Scheme could save you money. Figures use 2026/27 rates.
Tax and take-home pay
See what a sole trader keeps after income tax and Class 4 National Insurance.
Assumes self-employment is your only income. It leaves out Class 2 NI, student loans and pension contributions.
Your estimate
- Profit
- -
- Income tax
- -
- Class 4 National Insurance
- -
- Total tax and NI
- -
- Share of profit paid in tax
- -
- Set aside each month
- -
- You keep
- -
Every allowable expense you miss costs you at your top tax rate. That is why we claim them all.
CIS refund estimator
Contractors deduct tax from your pay. See if you have paid more than you owe.
Check your monthly CIS statements for the deducted total. Assumes CIS work is your only income.
Your estimate
- Profit
- -
- Income tax and Class 4 NI due
- -
- CIS already deducted
- -
- Estimated refund
- -
Deductions count towards your tax bill. A refund is paid after you file your Self Assessment return. See our CIS guide.
VAT Flat Rate Scheme comparison
Compare what you would pay HMRC under standard VAT accounting and under the Flat Rate Scheme.
Assumes your sales and purchases are standard-rated at 20%. Check current rates with HMRC before joining.
Your estimate
- Standard accounting: VAT to pay
- -
- Flat rate used
- -
- Flat Rate Scheme: VAT to pay
- -
- Difference
- -
A higher 16.5% rate applies to limited cost traders. Join only if turnover is expected to be £150,000 or less. See our VAT guide.
These calculators give estimates only, using 2026/27 rates. They are not tax advice or a tax calculation. Contact us for a personal figure.