How do I register for CIS as a subcontractor?

How do I register for CIS as a subcontractor? Register online with HMRC using your Unique Taxpayer Reference (UTR). No UTR yet? Register for Self Assessment as a subcontractor and HMRC sets up both. Once registered, contractors deduct 20% from your labour, not 30% (GOV.UK, October 2026). GOV.UK says you should register if you work for a contractor as a sole trader, a partner or the owner of a limited company. If you do not, contractors must deduct 30% from your labour instead of 20%. Employees do not register. Not online. If you have no Unique Taxpayer Reference, register as a new business for Self Assessment and choose 'working as a subcontractor'. GOV.UK says that registers you for Self Assessment and CIS at the same time. Ask your contractor for a replacement. If you cannot get one, for example because the contractor has gone out of business, GOV.UK says to write to HMRC with your details, the contractor's details and the dates you were paid. Read the full answer, with every source, at rightotax.co.uk.