Registering as a CIS Subcontractor

Key facts

CIS registration for subcontractors is voluntary — but strongly recommended.
Registered subcontractors have 20% deducted; unregistered subcontractors face 30% deductions.
You can register online or by phoning HMRC on 0300 200 3210.
You need a Unique Taxpayer Reference (UTR) and your National Insurance number to register.
Subcontractors with gross payment status receive payments with 0% deduction.

Why Register as a CIS Subcontractor?

While CIS registration for subcontractors is not legally required, the financial impact of not registering is significant:^[1]

Registration Status	Deduction Rate	On £1,000 Labour Payment	You Receive
Registered	20%	£200 deducted	£800
Unregistered	30%	£300 deducted	£700
Gross payment status	0%	£0 deducted	£1,000

The 10 percentage point difference between 20% and 30% can have a major impact on cash flow, especially for smaller businesses. While the extra deduction is recoverable at the end of the tax year, many subcontractors cannot afford to wait that long.

Tip: Registration is free and straightforward. There is no practical reason not to register as a CIS subcontractor if you carry out construction work for contractors.

How to Register

You can register as a CIS subcontractor through two channels:^[2]

Online Registration

Sign in to your HMRC online account (Government Gateway)
Navigate to the Construction Industry Scheme section
Select “Register as a subcontractor”
Enter your personal details, UTR, and National Insurance number
Confirm your registration

Phone Registration

Call the CIS helpline on 0300 200 3210 (Monday to Friday, 8am to 6pm). You will need:

Your Unique Taxpayer Reference (UTR)
Your National Insurance number
Your full name, address, and date of birth
For companies: company UTR and company registration number

Prerequisites for Registration

Before you can register as a CIS subcontractor, you must have a Unique Taxpayer Reference (UTR). If you do not have one, you need to register for Self Assessment first:^[2]

Business Type	How to Get a UTR	Typical Timeframe
Sole trader	Register for Self Assessment online at GOV.UK	UTR arrives within 10 working days
Partnership	Register the partnership for Self Assessment (SA400)	UTR arrives within 10 working days
Limited company	Register for Corporation Tax (automatic when incorporating via Companies House)	UTR arrives within a few weeks of incorporation

What Happens When a Contractor Verifies You

Once you are registered, contractors will verify you with HMRC before making their first payment. During verification, HMRC tells the contractor one of three things:^[3]

Matched — gross payment status: Pay the subcontractor in full with no deduction (0%)
Matched — net payment: Deduct at 20% from the labour element
Unmatched: Deduct at 30% — this happens if you are not registered or HMRC cannot match your details

Important: If your details do not match HMRC’s records — for example, your name or UTR is slightly different — you may come back as “unmatched” and face 30% deductions even though you are registered. Always ensure your details with HMRC are accurate and up to date.

After You Are Registered

Once registered, you should:^[1]

Provide your UTR and NI number (or company registration number) to every contractor you work for, so they can verify you
Keep all payment and deduction statements issued by contractors — you need these to reclaim CIS deductions
File your Self Assessment tax return (or Corporation Tax return), reporting your CIS income and claiming credit for deductions suffered
Keep business records including invoices, bank statements, and expense receipts for at least 5 years after the SA filing deadline

Upgrading to Gross Payment Status

If your business is well-established and has a good compliance record, you may be able to apply for gross payment status, which means contractors pay you in full with no CIS deductions. You must pass three tests:

Turnover test — minimum £30,000 net turnover (individual), or £30,000 per partner (partnership), or £30,000 per relevant person (company)
Compliance test — all tax returns filed on time, all tax paid on time
Business test — you carry on a business through a bank account

See our detailed article on Gross Payment Status for full details.

Common Registration Issues

Issue	Solution
No UTR yet	Register for Self Assessment first; UTR arrives in about 10 working days
Name mismatch	Ensure the name on your CIS registration exactly matches your Self Assessment records
Lost UTR	Call HMRC on 0300 200 3310 (Self Assessment helpline) to get a reminder
Company recently incorporated	Wait for HMRC to issue the company UTR (usually within a few weeks), then register
Partnership registration	Register the partnership (using the partnership UTR), not the individual partners

Frequently Asked Questions

Do I have to register as a CIS subcontractor?

No, registration is voluntary. However, if you do not register, contractors must deduct 30% from your payments instead of 20%. Since the deductions are advance payments of tax, you will get the money back eventually — but your cash flow will be significantly worse at 30% than at 20%.

How do I register as a CIS subcontractor?

You can register online through your HMRC personal tax account (Government Gateway) or by calling the CIS helpline on 0300 200 3210. You will need your UTR, National Insurance number, and personal details.

How long does CIS registration take?

If you already have a UTR and register online or by phone, the registration is usually effective immediately. If you need to apply for a UTR first, allow at least 10 working days for it to arrive before you can complete your CIS registration.

Can a limited company register as a CIS subcontractor?

Yes. Limited companies, sole traders, partnerships, and individuals can all register as CIS subcontractors. Companies need their company UTR and company registration number to register.

Sources

What you must do as a CIS subcontractor — GOV.UK
Register as a CIS subcontractor — GOV.UK
Construction Industry Scheme (CIS) — GOV.UK