More recently HMRC has stated that contractors of third party intermediaries who would have been an employee if they were providing their services directly to the client are now required to pay broadly the same Income tax and NI as employees.
Critchleys payroll software has now been updated to be able to accommodate this need for new clients and report any Tax and NI deductions from the contractor to HMRC through the normal FPS submission.
If this is something you require assistance with please do get in touch.