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IR35 Calculator

See exactly how much more you take home outside IR35 vs inside IR35. Enter your contract day rate and get a side-by-side comparison in seconds.

·CalcKit·Updated
IR35 CalculatorFree · No signup
£

Your daily contract rate

Days worked per year (220 = ~46 weeks)

How does IR35 status affect your take-home pay?

IR35 Calculator is designed specifically for UK businesses and individuals. All calculations use current 2025/26 rates and follow HMRC guidelines.

Completely free with no signup required. Results are instant and calculated in your browser — no data is sent to our servers. For significant financial decisions, consult a qualified UK accountant or financial adviser.

How do you use the IR35?

  1. 1Enter your contract day rate and the number of days you work per year. The calculator shows your take-home pay inside IR35 (treated as employment income) versus outside IR35 (dividend extraction through a limited company).
  2. 2Inside IR35, you pay full PAYE income tax and National Insurance on your contract income, with no ability to extract profits as dividends. Outside IR35, you pay yourself a low salary and take the rest as dividends at lower tax rates.
  3. 3If your contract is inside IR35, consider negotiating a higher day rate to compensate for the additional tax cost. The financial difference between inside and outside IR35 is typically £10,000–£25,000 per year depending on your rate.

Use alongside

Pair this tool with our other free calculators: Ecommerce Profit Calculator, Contractor vs Employee Calculator.

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Rates and thresholds sourced from HMRC and GOV.UK. Updated for the 2025/26 tax year.

Also known as

ir35 calculator ukir35 calculatorinside ir35 take home pay calculatoroutside ir35 take home pay calculatorir35 inside vs outside calculatorir35 tax calculator uk

Inside vs Outside IR35 — Take-Home Pay by Day Rate

How much you keep inside vs outside IR35 at common contractor day rates, based on 220 billable days a year. Outside IR35 assumes a £12,570 salary plus dividends through a limited company; inside IR35 assumes the full contract value is taxed as deemed employment income.

Day RateAnnual Gross (220 days)Outside IR35 Take-HomeInside IR35 Take-HomeAnnual Difference
£300/day£66,000.00£47,034.05£43,530.40£3,503.65
£350/day£77,000.00£54,562.17£48,953.40£5,608.77
£400/day£88,000.00£62,090.30£54,376.40£7,713.90
£450/day£99,000.00£69,618.42£59,799.40£9,819.02
£500/day£110,000.00£77,146.55£65,222.40£11,924.15
£550/day£121,000.00£84,674.67£70,285.40£14,389.27
£600/day£132,000.00£92,202.80£74,773.40£17,429.40
£650/day£143,000.00£99,730.92£79,261.40£20,469.52
£700/day£154,000.00£107,259.05£84,074.90£23,184.15
£800/day£176,000.00£122,315.30£93,985.90£28,329.40

Figures use 2025/26 rates, 220 billable days, and £2,000 annual expenses. Enter your exact day rate and billable days in the calculator above for a personalised breakdown.

Frequently Asked Questions

IR35 (also called the off-payroll working rules) is HMRC legislation designed to ensure contractors who work like employees pay similar income tax and National Insurance as employees. If your contract falls "inside IR35", you are taxed as an employee. "Outside IR35" means you can operate tax-efficiently through a limited company.

The difference is significant. At a £500/day rate over 220 days (£110,000 gross), outside IR35 typically gives you around £20,000–£25,000 more take-home pay per year than inside IR35. Our calculator shows the exact figure for your specific day rate.

Since April 2021 (off-payroll working rules), for medium and large private sector engagers, the end client determines IR35 status — not the contractor. Small companies are exempt and the contractor still determines their own status. HMRC's CEST tool at gov.uk can help assess status, but many contractors also seek legal opinion.

If HMRC determines a contract should have been inside IR35, they can demand back-payment of income tax and National Insurance, plus interest and penalties. The liability can fall on the engager (if they made the determination) or the contractor. Always get a proper contract review from an IR35 specialist.

Yes. IR35 status is determined contract by contract, not per person or company. You could have one contract inside IR35 and another outside simultaneously. You must account for the income and tax separately for each contract.

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Last updated: 1 April 2026 · Rates for 2025/26 tax year