IR35 Tax Calculator – Inside or Outside? (2026/27)

Use our IR35 calculator to estimate your tax liability and net income inside vs outside IR35 if you work via a limited company.

Enter your details to see how IR35 affects your take-home pay.

How to use the calculator

• Fill in the blue boxes to calculate your net income – inside and outside IR35.
• The calculator assumes you work 5 days per week, 44 weeks per year, so it is best used to show the approximate difference in taxation between the two scenarios.
• Pension contributions are payments your limited company makes directly into a pension scheme on your behalf.

This calculates the financial impact of IR35 if you work through your own limited company.

If you’re working through an umbrella company, use our umbrella company calculator.

What changed for the 2026/27 tax year?

We have included the 2p rise in the basic higher rate dividend tax bands from April 6th 2026.

You will notice that, after years of tax increases, the difference in tax home between inside and outside IR35 scenarios is smaller than ever.

2026/27 IR35 Tax Calculator

Get IR35 protection for under £99 per year

Important note

This calculator shows the effect of the original IR35 rules on your income (Section 8 of the ITEPA 2003), not the April 2021 ‘Off-Payroll’ rules (Section 10).

The original IR35 rules only apply if your client meets the definition of a small company.

If your work is caught by IR35 and your client is a small company, your company can claim a fixed ‘5% allowance’, equal to 5% of your annual turnover, to cover business expenses (such as accountancy fees). This is used to work out your inside-IR35 ‘deemed payment’.

However, Corporation Tax may still be payable on this 5% allowance, although in practice most contractors incur at least as much in allowable business expenses each year.

So, the Corporation Tax amount in the summary for inside-IR35 will become zero if you incur business expenses equal to or greater than 5% of turnover.

The 5% allowance is unavailable if your work is subject to the Off-Payroll rules (effective from April 2017 for public sector clients and from April 2021 for private sector clients).

What’s included and excluded in our calculations + other notes

• Read our complete guide to IR35 for background information on the Intermediaries Legislation.
• For simplicity, the calculator ignores the Employment Allowance.
• All tax rates used in the calculations are for the 2026/27 tax year.
• If you live in Scotland, different income tax bands and rates apply, so your total tax bill may differ from that displayed above.
• Our ACA-qualified accountant created our calculator. However, you should always consult your accountant before using any information published on our site.