How to Get a CIS Number

Learn how to get a CIS number in the UK, including how to register with HMRC and what details contractors need to verify your status.

How Do I Get a CIS Number?

If you work in the UK construction industry as a subcontractor or contractor, you may have been told you need a CIS number. This number is essential for getting paid correctly under the Construction Industry Scheme (CIS) and for staying on the right side of HMRC. But what exactly is a CIS number, and how do you get one?

In this article, we explain what a CIS number is, how to apply for it, who needs one, and what steps you need to take to register properly. Whether you're just starting out as a sole trader or setting up a construction business, getting your CIS number sorted early will make your life much easier.

What Is a CIS Number?

A CIS number refers to your Unique Taxpayer Reference (UTR), which HMRC uses to identify you for CIS purposes. When people say "CIS number," they usually mean the UTR that’s linked to your CIS registration.

There is no separate or special number called a "CIS number" issued by HMRC. Instead, your UTR is the unique identifier used when contractors verify your status, report payments and calculate tax deductions.

Your UTR is a 10-digit number, sometimes shown with a ‘K’ at the end, and is issued when you register for Self Assessment as self-employed or register your limited company for tax.

Who Needs a CIS Number?

You will need a CIS number if you are:

  • A self-employed subcontractor carrying out construction work for contractors

  • A limited company acting as a subcontractor or contractor in the construction industry

  • A contractor who hires subcontractors and pays them for construction services

If you are a subcontractor and not registered under CIS, your payments will be subject to a higher tax deduction of 30 per cent instead of the standard 20 per cent. If you are registered, contractors will deduct 20 per cent unless you qualify for gross payment status, in which case you receive full payment with no deduction.

How to Get a CIS Number as a Sole Trader

Step 1: Register as Self-Employed

To get your UTR, you must first register as self-employed with HMRC. You can do this online at gov.uk/register-for-self-assessment. You will need:

  • Your full name and address

  • National Insurance number

  • Date of birth

  • Details about your business (e.g. when you started working for yourself)

After registration, HMRC will send your UTR by post. This usually takes about 10 working days.

Step 2: Register for CIS

Once you have your UTR, you can register for the Construction Industry Scheme. Go to gov.uk/what-you-must-do-as-a-cis-subcontractor and log in using your Government Gateway credentials.

During the registration process, make sure you select the correct option:

  • Subcontractor

  • Contractor

  • Or both, if you are doing both roles

You’ll need your UTR, National Insurance number, and bank details to complete the process. After registration, you’ll receive confirmation from HMRC. Your UTR now acts as your CIS number.

How to Get a CIS Number as a Limited Company

If you operate through a limited company, the process is slightly different.

Step 1: Register Your Company

Set up your company with Companies House and register for Corporation Tax with HMRC. As part of this process, HMRC will issue your company with a UTR.

Step 2: Register for CIS

Once you have the company UTR, you must register for CIS either as a contractor, subcontractor, or both. You can do this online through your HMRC Business Tax Account. You will need:

  • Company UTR

  • Company registration number

  • Director details

  • Business bank account information

If you are acting as a subcontractor, this UTR will be used by contractors to verify your CIS status.

How Long Does It Take to Get a CIS Number?

  • UTR: Usually arrives within 10 working days after registering for Self Assessment or Corporation Tax

  • CIS registration confirmation: Often immediate online, but formal confirmation by post may take a few more days

If you are applying close to the end of the tax year or during a busy period, it may take longer.

How Do Contractors Use My CIS Number?

Once you are registered, contractors will use your UTR to verify your CIS status with HMRC. This helps them determine:

  • If you are registered as a subcontractor

  • What deduction rate to apply (20 per cent, 30 per cent, or 0 per cent for gross payment status)

You do not need to show a physical card or document. Just ensure your contractor has your correct UTR and full details so they can verify you properly.

What If I Lose My CIS Number?

If you lose your UTR or are unsure of your CIS registration, you can:

  • Log in to your HMRC Personal Tax Account at gov.uk/personal-tax-account

  • Check old letters or emails from HMRC (the UTR often appears on Self Assessment or Corporation Tax correspondence)

  • Call the HMRC CIS helpline on 0300 200 3210

Make sure you have your National Insurance number and other ID details ready when calling.

Final Thoughts

Although there is no separate card or number labelled "CIS number," your Unique Taxpayer Reference (UTR) serves this purpose once you are registered for the Construction Industry Scheme. Whether you are a sole trader or running a limited company, registering with HMRC and securing your UTR is the first step to getting paid correctly and avoiding higher tax deductions.

Take time to register properly and keep your details safe, as your UTR is essential for managing your construction tax obligations.