Registering for CIS is one of the first things to do when you start working in construction under your own name or company. Without it, you get deducted at 30% instead of 20%, which makes a big difference on every payment. Registration is simple and takes about 20 minutes online.
Do you need to register for CIS?
You must register if you do construction work for a contractor and get paid as a business, not as an employee. That includes sole traders, partnerships, and limited companies. You do not register if you work through an umbrella company under PAYE.
Registration is optional only in the sense that you can still do the work without it. But unregistered subcontractors are deducted at 30% instead of 20%. That costs more on every invoice during the year. You do get it back at year end through self-assessment, but the cash still sits with HMRC until then.
If you are thinking about umbrella PAYE instead of self-employment, you do not need CIS registration at all. An umbrella company employs you under PAYE, so CIS deductions do not apply to employed workers.
See the Construction Industry Scheme for a full explanation of who CIS applies to.
What do you need before registering?
Before you register as a CIS subcontractor, you need:
- A Unique Taxpayer Reference (UTR). Every self-employed person and limited company has one. If you have not registered for self-assessment yet, do that first. HMRC sends your UTR by post in about 10 working days.
- A Government Gateway account. This is your HMRC online portal. You need a Government Gateway user ID to register for CIS and manage everything after that.
- National Insurance number. Required for sole traders. Your NI number is on your payslip from any previous job.
- Legal business name and address. For sole traders, that means your name and address. For companies, it means the registered company name and Companies House registration number.
For limited companies, HMRC may ask for all directors’ UTRs during the process, especially if you later apply for GPS.
Step by step: how to register online
Step 1: Log in to your HMRC Government Gateway account at gov.uk. If you do not have one, create one. You will verify your identity with photo ID or existing HMRC credentials.
Step 2: Navigate to CIS. In the Government Gateway dashboard, look for “Construction Industry Scheme (CIS)” under your taxes. Select “Register as a subcontractor.”
Step 3: Enter your details. You will need your UTR, NI number, legal name, and the type of construction work you do. HMRC asks for the work type so it can classify your activity correctly.
Step 4: Submit. HMRC usually processes the registration within a few working days. You will get confirmation.
Step 5: Tell the contractors who pay you. Once you are registered, the contractors who pay you must verify your status before the first payment. They do that through HMRC’s verification system. HMRC confirms your registration and gives them your rate, which is usually 20%.
You do not need to do anything else. The verification happens on the contractor’s side.
What happens after registration?
Once you are registered, contractors who verify you are told to use the 20% rate. Payments you received before registration at 30% can still be corrected at year end through self-assessment.
Keep a record of your registration date. Any payments you received before that date at 30% are still creditable against your tax bill. They show up on your self-assessment as CIS deductions suffered.
HMRC keeps your registration active as long as you stay compliant. You do not need to renew it every year. But you do need to keep filing self-assessment returns and stay on top of your tax.
What are the deduction rates once you are registered?
Registered subcontractors are deducted at 20% on the labour element of their payments. Unregistered subcontractors are deducted at 30%. GPS holders receive payments with no deduction.
See the full detail on CIS deduction rates, including how materials exclusions work and how deductions are credited against your annual tax.
Do you also need to register as a contractor?
Only if you pay other subcontractors yourself. Registering as a subcontractor and registering as a contractor are separate. If you take on subcontractors of your own, you must also register as a CIS contractor with HMRC and start filing monthly returns.
Many construction businesses do both. They receive payments as a subcontractor and make payments to others as a contractor. In that case, both registrations are needed.
Can you register by phone?
Yes. HMRC’s CIS helpline can take subcontractor registrations. Call the helpline and have your UTR, NI number, and business details ready. Online registration is faster and gives you an immediate confirmation record.
The CIS helpline number is available on gov.uk under “Construction Industry Scheme.” Call it during HMRC’s published opening hours.
Contact the CIS payroll service if you need help registering or want to discuss CIS payroll management for your construction business.
Frequently Asked Questions
Do I need to register for CIS as a subcontractor?
You are not legally required to register, but unregistered subcontractors are deducted at 30% instead of 20% on every payment. Registration lowers your deduction rate and takes about 20 minutes online.
What do I need to register for CIS?
A Unique Taxpayer Reference (UTR), a Government Gateway account, your National Insurance number, and your legal business name and address. You need a UTR before you register, so register for self-assessment first if you do not have one.
How do I register for CIS as a subcontractor?
Log in to your HMRC Government Gateway account, navigate to CIS, select “Register as a subcontractor,” enter your details, and submit. HMRC confirms registration within a few working days.
Do contractors need to do anything after I register?
Yes. Before your first payment, each contractor who pays you must verify your details through HMRC’s verification system. HMRC confirms your registration and gives them your deduction rate.
Do I need to register as both a subcontractor and a contractor?
Only if you also pay other subcontractors yourself. Subcontractor and contractor registrations are separate. If you receive payments and make payments to others, you need both.
