UK IR35 Calculator
Compare your take-home pay for contracts Inside vs Outside IR35 for the 2025/2026 tax year.
Usually around 220-230 days
Only deductible Outside IR35
Inside IR35
Taxed as an employee (PAYE)
Outside IR35
Taxed as a business (Sole Trader proxy)
Frequently Asked Questions
How to use this calculator
1. Enter your daily contract rate.
2. Enter the number of days you expect to work in the year (typically 220-230 days).
3. Enter your estimated annual business expenses (only applicable if Outside IR35).
4. Compare the net take-home pay between the two scenarios.
Understanding your results
Inside IR35: Assumes you are taxed as an employee via PAYE. Employer NI is deducted from your gross rate, followed by Employee NI and Income Tax. Expenses are generally not allowable.
Outside IR35: Assumes you operate as a self-employed individual (sole trader proxy used here for simplicity). You can deduct expenses before tax, and you pay Self-Employed NI rates, resulting in higher take-home pay.