
CIS contractors and the IR35 boundary
Where the Construction Industry Scheme ends and IR35 begins, and why a CIS deduction does not settle your employment status

Reading an umbrella payslip line by line — the assignment rate, the employment costs and what finally reaches you.
The assignment rate is what the agency pays the umbrella. Every cost of employing you is met from it before your gross pay is calculated.
Most confusion about umbrella payslips comes from reading the assignment rate as a salary.
What is left is your gross pay. Income tax, employee National Insurance and your own pension contribution come out of that figure, and holiday pay should be visible as its own line either way it is handled.
Employment costs plus gross pay should equal the assignment rate. If they do not, ask — a compliant provider can show the working on request.

Daniel Okafor
leads contractor payroll operations at Promultis
Daniel Okafor runs the payroll operation that pays several thousand contractors every week, and he built most of it. He joined Promultis from a large umbrella provider, where he was responsible for RTI submissions and auto-enrolment across a book of forty agencies. Daniel works closely with recruitment partners on onboarding, same-day payments and the reporting hirers need for their own audits. He writes about the practical side of contractor engagement — the parts that decide whether a worker stays past their first assignment.

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