How to register for CIS as a subcontractor

Registered subbies have 20% taken off. Unregistered subbies have 30% taken off.

Who should register

If you work for a contractor and you are a sole trader, own a limited company, or are a partner, you should register. The deductions count towards your own tax and National Insurance bill.

Before you start: get a UTR

You need a Unique Taxpayer Reference (UTR). No UTR yet? Register for Self Assessment and choose "working as a subcontractor". That registers you for Self Assessment and CIS together.

What you need

Your legal business name, and trading name if different.
Your business UTR.
Your VAT number, if VAT registered.
The date you started trading.
Depending on your business: your National Insurance number, the Company Registration Number, or the registering partner's UTR and National Insurance number.

How to register

Online (quickest)
Sign in to HMRC's online form for subcontractors. It registers you to be paid with 20% taken off.
Or by post
If you cannot use the online form, GOV.UK has a postal route for a sole trader, a partnership and a limited company.
Give your details to each contractor
Your contractor verifies you with HMRC using them, then takes off the right rate.

Good to know

If you also pay subbies yourself, register as a contractor too.
Based abroad but working in the UK? You should still register.
Want nothing taken off? Apply for gross payment status instead. That registers you for CIS as well.
Giving false information can lead to a fine, for you and for anyone who helps.

Limited company? Read CIS for limited company subcontractors.

Try the CIS calculator

A guide, not tax advice

We checked this against the sources below on 31 Oct 2026. Rules change. You stay responsible for your own tax, so check anything unusual with your accountant or on gov.uk.

Sources

GOV.UK, "What you must do as a Construction Industry Scheme (CIS) subcontractor" (gov.uk/what-you-must-do-as-a-cis-subcontractor)
GOV.UK, "What you must do as a CIS subcontractor: how to register" (gov.uk/what-you-must-do-as-a-cis-subcontractor/how-to-register)

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