Use form CIS301 if you’re a sole trader to register as a Construction Industry Scheme (CIS) subcontractor for payment under deduction.
You can also register as a subcontractor online.
If you’re acting on someone else’s behalf you must use form CIS301. Only the individual can register as a subcontractor online.
Use HM Revenue and Customs guidance explaining the duties of both contractors and sub-contractors (CIS340) within the CIS.
Use these CIS forms to register: