IR35 Calculator
Instantly compare your net take-home pay Inside IR35 vs Outside IR35. See the exact breakdown of taxes, NI, and fees.
Contract Details
Inside IR35
PAYE via Umbrella
Outside IR35
Limited Company (LTD)
The IR35 Impact
Operating Outside IR35 nets you +£0 more per year.
Understanding IR35: Inside vs Outside
The UK's IR35 legislation (off-payroll working rules) is designed to combat tax avoidance by workers supplying their services to clients via an intermediary, such as a Limited Company (LTD), but who would be classed as an employee if the intermediary was not used.
What does "Inside IR35" mean?
If your contract is deemed Inside IR35, HMRC considers you an employee for tax purposes. This means you must pay standard Income Tax and National Insurance (NI) exactly like a permanent employee. Usually, you will need to work through an Umbrella Company. The Umbrella Company acts as your employer, deducting Employer NI, Apprenticeship Levy, and their own weekly margin from your gross day rate before your gross salary is even calculated.
What does "Outside IR35" mean?
If your contract is Outside IR35, you are running a genuine business. You operate through your own Limited Company and have full control over your tax strategy. The most tax-efficient and common method used by UK contractors is to pay themselves a low base salary (typically up to the Primary Threshold of £12,570 to avoid Income Tax while securing state pension credits) and extract the rest of the company profits as Dividends, which are taxed at a lower rate.
How accurate is this calculator?
Our IR35 Calculator utilizes standard 2026/27 UK tax bands to provide a highly accurate estimation. For the "Outside IR35" calculation, the engine assumes the standard optimum director's salary. It calculates Corporation Tax (using the 19% small profits rate for simplicity on standard contractor revenues) and standard Dividend tax brackets. As this is processed 100% locally via Client-Side JavaScript, your financial rates are never tracked or saved.