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Self Employed Calculators Free UK Tax Tools · 2025/26
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IR35 Calculator

Compare your take-home pay inside IR35 versus outside IR35 based on your contract day rate for 2025/26.

Typical full-year contractor: 220–240 days.

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What Is IR35?

IR35 (also called the off-payroll working rules) is legislation designed to ensure contractors who work like employees pay similar levels of tax and National Insurance as employees. If your contract falls "inside IR35," you are treated as a deemed employee for tax purposes.

Inside IR35 vs Outside IR35

Outside IR35

  • Work through your limited company
  • Pay salary + dividends
  • Pay corporation tax on profits
  • More take-home pay

Inside IR35

  • Treated as an employee for tax
  • Pay income tax + employee NI
  • Employer NI also deducted from your rate
  • Significantly lower take-home

How Is IR35 Status Determined?

HMRC looks at three key factors: substitution (can you send someone else?), control (who controls how the work is done?), and mutuality of obligation (is there an obligation to offer or accept work?). HMRC's CEST tool can help determine status.

Protect Your IR35 Position

These specialist services offer IR35 insurance, reviews, and contractor accountancy.

We may earn a commission if you sign up via these links, at no extra cost to you.

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