Right to work checks: what contractors must do when hiring subcontractors

The penalties for employing someone who does not have the right to work in the UK are significant — a civil penalty of up to £60,000 per worker, and potentially a criminal conviction. These rules apply to anyone you hire as a worker, which for most trade contractors includes subcontractors who work under your direction on your contracts.

Understanding who is legally classed as a worker (and therefore requires a right to work check) versus a genuinely self-employed subcontractor (where the obligation sits with them) is one of the more confusing areas for trade businesses. This article explains the rules, who they apply to, and exactly what you need to do.

What is a right to work check?

A right to work check is a process where you verify, before someone starts working for you, that they have the legal right to work in the UK. You do this by checking their documentation, copying it, and keeping a record of when you checked it.

The purpose is to give you what the Home Office calls a statutory excuse against a civil penalty. If you carry out the check correctly and the person turns out to be working illegally, you will not be fined. If you fail to carry out a proper check, you are liable — even if you genuinely did not know the person had no right to work.

Do right to work checks apply to subcontractors?

This is the part many contractors get wrong. The legal answer depends on the employment status of the person you are engaging.

If you engage someone as a worker — they work under your supervision and direction, you tell them what to do and when, and they work as part of your team — then you are their employer for immigration purposes and must carry out a right to work check.

If you engage someone who is genuinely self-employed — they operate their own business, bring their own tools, decide how the work is done, and invoice you — then the obligation to have the right to work sits with them, not with you.

The problem is that this line is often blurry. The Home Office takes a similar view to HMRC on worker classification: if the person looks and behaves like an employee, they will treat them as one regardless of what your contract says. The practical advice is: if in doubt, do the check anyway. It costs very little and gives you protection.

What documents do you need to check?

There are two lists of acceptable documents. List A documents confirm an unlimited right to work and only need checking once. List B documents have time limits and require follow-up checks.

List A (one-time check)

• A British or Irish passport (current or expired)
• A UK birth or adoption certificate plus a National Insurance number document
• A certificate of naturalisation or registration as a British citizen

List B (repeat checks required)

• A current passport with a time-limited visa or biometric residence permit
• A share code from the Home Office online verification service

For EU, EEA, and Swiss nationals who came to the UK before 31 December 2020, verify their status using the Home Office online right to work checking service, which uses their share code to confirm settlement or pre-settlement status. Full details of acceptable documents are in the Home Office employer guide to right to work checks on gov.uk.

How to carry out a right to work check

There are three ways to carry out a right to work check:

Manual document check

1. Ask the person to provide original documents from the acceptable lists
2. Check the documents are genuine and belong to the person (compare photos, check for tampering)
3. Make a clear copy — photocopy or scan
4. Record the date you carried out the check
5. Retain the copy for as long as the person works for you, plus two years after they leave

Home Office online checking service

For people who have a share code, you can verify their right to work online at gov.uk/view-right-to-work. You need the worker date of birth and share code. Save the result as a screenshot or PDF.

Identity Document Validation Technology (IDVT)

Certified Identity Service Providers can carry out digital right to work checks for British and Irish citizens using biometric data. This is useful for businesses that regularly take on new workers and want a simplifyd process.

Civil penalties and when they apply

The penalty structure as of 2024 is: up to £45,000 per illegal worker for a first offence, and up to £60,000 for repeat offences. If you carried out a proper right to work check before the person started work, you have a statutory excuse and will not face a civil penalty — even if the documents turned out to be fraudulent, provided they appeared genuine to a reasonable person.

Criminal liability applies where you knew or had reasonable cause to believe the person had no right to work. This can result in unlimited fines and up to five years in prison.

CIS and right to work checks

When you register a subcontractor under the Construction Industry Scheme, you verify their identity and tax status — but this is completely separate from a right to work check. CIS registration does not substitute for a right to work check. For CIS-related calculations, use the CIS deduction calculator.

Keeping records

Whatever method you use, keep a record of: the document(s) checked (copy), the date the check was carried out, and for online checks, a printout or screenshot including the date. Records must be kept for the duration of employment plus two years after the person stops working for you. They are subject to GDPR and must be stored securely.

Frequently asked questions

Do I need to check right to work for a labour-only subcontractor?

It depends on whether they are genuinely self-employed. If they operate their own business and invoice you, the obligation sits with them. If they work under your supervision, treat them as a worker and carry out a check.

What if a subcontractor refuses to provide documents?

Do not allow them to start work. Accepting verbal assurances is not a substitute for a proper check and will not give you a statutory excuse against a penalty.

Do I need to check UK nationals?

Yes. British and Irish citizens still need to provide a document confirming their right to work — typically a UK or Irish passport. A birth certificate alone is not sufficient; it must be combined with evidence of NI number.

How often do I need to repeat right to work checks?

For List A documents, check once. For List B (time-limited), carry out a follow-up check before the existing permission expires — typically every 12 months if the visa is renewed annually.

Can I use a photocopy instead of the original document?

No. You must see the original document in person or use the Home Office online service. A photocopy is not acceptable for the initial check, though you must make a copy once you have seen the original.