GOV.UK
What you must do as a Construction Industry Scheme (CIS) contractor
9. Tell HMRC about changes
You must tell HM Revenue and Customs (HMRC) if you:
- change address (as an individual or business)
- stop using subcontractors temporarily because you’re using your own employees to carry out work
- change your business structure - eg from sole trader to limited company or vice versa
- stop trading, or a contractor dies
You must tell HMRC within 90 days if you’re a multiple contractor and you take on all or part of another contractor’s business.
Call the Construction Industry Helpline (CIS) to report changes.