Each month, contractors must send HMRC a complete return of all payments made to all subcontractors within the CIS in the preceding tax month (FA 2004, s. 70 and SI 2005/2045, reg. 4). This is regardless of whether the subcontractors were paid gross or net of either the standard or higher deduction. Monthly returns must reach HMRC within 14 days of the end of the tax month they are for.
In order to complete the monthly return, contractors must do the following:
•check the pre-printed names and unique taxpayer reference (UTR) numbers of all the subcontractors they have paid in the month;
•leave blank any pre-printed entries for subcontractors they have not paid in the month;