What statutory deductions are made and why?

All employer and employee costs must be paid out of the turnover we receive from the agency, this applies to Employer’s NI, holiday pay, auto-enrolment pension deduction (if appropriate) and our margin.
Agencies uplift the rate that is paid to an Umbrella Company specifically to cover these costs.
Once these and any allowable expenses have been deducted then the remainder is paid as your wage (hours at National Minimum Wage) and profit-related pay, which are subject to PAYE tax and Employee’s NI.