IR35 Calculator 2026/27 — Inside vs Outside

From April 2021, medium and large engagers (end-clients) are responsible for assessing IR35 status. If ruled inside IR35, the contractor is treated as a deemed employee — paying Income Tax and NICs through PAYE without the benefits of employment.

Outside IR35 contractors can pay themselves a small salary and take the remainder as dividends, significantly reducing their tax bill. The difference is typically £8,000–£25,000/year at standard contracting rates.