To register as a contractor under the Construction Industry Scheme (CIS), you will need to register as an employer and you will need your business UTR, your National Insurance number, VAT registration number (if registered), and your legal business name1. You can register here on the HMRC website1.
Subcontractors who are operating as sole traders can register for CIS through their Government Gateway ID
It’s important to note that failure to register as a CIS contractor or comply with the rules of the scheme can result in penalties and fines.