A UTR (Unique Taxpayer Reference) is a 10-digit number that HMRC assigns to every individual and company registered for Self Assessment or Corporation Tax. In the context of CIS, the UTR is the primary identifier that ties a subcontractor to their HMRC record and determines what deduction rate a contractor must apply.
When a contractor verifies a subcontractor through the HMRC CIS online service, they enter the subcontractor's UTR (along with the subcontractor's name and, for a company, the company registration number). HMRC then returns one of three outcomes: the subcontractor holds Gross Payment Status (deduct at 0%), the subcontractor is registered (deduct at 20%), or the subcontractor is not found (deduct at 30%).
The UTR is therefore the key document a subcontractor must provide to every new contractor before the first payment. Without it, the contractor cannot verify and defaults to the 30% unregistered rate.
Key points about UTRs in CIS:
- Sole traders have a personal UTR (10 digits, usually starting with a number such as 1 or 2). This is the same UTR used for Self Assessment.
- Limited companies have a company UTR, separate from the directors' personal UTRs. Both the company UTR and the Companies House registration number are needed for verification.
- Partnerships have a partnership UTR as well as individual UTRs for each partner. The partnership UTR is used for CIS verification.
- A UTR is issued when a person first registers for Self Assessment or when a company registers for Corporation Tax. New sole traders working in construction should register for Self Assessment promptly so their UTR arrives before they need to give it to a contractor.
If you have lost your UTR, it appears on previous HMRC correspondence, tax returns and the HMRC app. See how to register for CIS for the full registration process, which covers getting your UTR as the first step.