Right to Work Construction · run by Sovereign Plus

Right to work checks for construction subcontractors (2026)

A plain guide for contractors who use CIS subbies, gangs and labour from other firms. Updated for the rules that started on 1 October 2026.

Last checked against GOV.UK: . General information, not legal advice.

The free official route. You can do every right to work check yourself, free, on GOV.UK. Start at Checking a job applicant's right to work. For a share code, use Check a job applicant's right to work: use their share code. If the person cannot show their status, use Use the Employer Checking Service.

In short

  • Employees always need a right to work check before they start.
  • Since 1 October 2026, a self-employed subbie you take on to do work you have agreed to do for someone else also needs a check. The law calls them an "individual sub-contractor".
  • If you use another firm (a limited company subbie, a labour supplier, a gang master) to do work you have agreed to do for someone else, that firm checks its people. You must have the right contract terms and ID checks to protect yourself.
  • Deals made before 1 October 2026 are not brought in just because the work carries on.
  • Fines start at £45,000 per worker for a first breach and £60,000 for a repeat.

Why this matters for CIS firms

Before 1 October 2026 the duty to check was only for employees. Most CIS subbies are self-employed, so many contractors did not check them. The Border Security, Asylum and Immigration Act 2025 changed that. Section 48 widened who counts as an "employer" for right to work checks (Right to work checks: an employer's guide (1 October 2026)).

The Home Office looks at how the work is really set up, not the label. Calling someone "self-employed" does not take them out. A tax status decision such as IR35 does not decide it either (Employer's guide, Annex C).

Who needs a check?

Employees

You must check every employee before they start work. This has been the law since 29 February 2008 (Checking a job applicant's right to work).

Self-employed CIS subbies

An "individual sub-contractor" is a person who has a contract with you to do work, where you have a contract with someone else to do that work (Employer's guide, definitions). On a building site that is a normal set-up: the client hires you, and you take on a subbie.

If you took them on, or agreed a new deal, on or after 1 October 2026, a check is needed by law. If the deal was made before, the law does not require one just because work carries on. But a new or changed deal may count as new (Employer's guide, Annex C).

A trader who runs their own business and works straight for the public is not in scope. The Home Office example is a self-employed plumber fixing a tap for a homeowner (Employer's guide, Examples 5 and 6).

Subbies that trade as a limited company

If you buy a job from someone's company for your own use, you do not need to check the person (Employer's guide, Examples 5 and 6). If you use their company to do work you have agreed to do for someone else, "extended liability" can apply (see below).

Agency and supplied labour

In a normal agency set-up, the agency is the employer and does the check. You do not need to repeat it (Employer's guide, Annex C). If you use other firms to supply people for a contract you hold with a client, extended liability can apply. The Home Office uses a building firm as its example (Employer's guide, Example 7).

Extended liability: when you are in a contract chain

The Home Office first looks for the firm that directly took on the worker. If it cannot find them, or the rules were not followed, it can fine a firm further up the chain (Code of practice, section 3).

To protect yourself you must meet the "prescribed requirements" before the work starts:

  1. A written statement of contract terms. The firm you use must agree to: do proper right to work checks; not subcontract without your written OK, and pass the same rules down; let you audit their checks; let you act (for example suspend or end the contract) if illegal working is found; and help any Home Office investigation, including details of the chain.
  2. Substitution controls, if a worker can send someone else in their place. Every substitute must be checked before they work, and you cannot leave the checking to the worker.
  3. ID checks on site. A fair system to make sure the person working is the person who was checked. Examples include site passes, face checks by a registered provider, sign-in systems, training records, and checking ID again at set times, at least once in any 24 hours of work.

You do not need to check every worker in the chain yourself. You can rely on other firms' systems if you take reasonable steps to make sure they work (Employer's guide, Annex C). Existing supplier checks cannot replace the written statement.

How to do the check

There are three ways. The check must be done before the work starts.

1. Online, with a share code (most non-British workers)

  1. The worker gets a share code from Prove your right to work to an employer. It starts with W and lasts 90 days.
  2. You enter it with their date of birth at Check a job applicant's right to work: use their share code.
  3. Check the photo is the person, and check any limits on the work or hours.
  4. Save the profile page as a PDF.

People with an eVisa can only prove their right to work this way. British and Irish citizens cannot get a share code (Checking a job applicant's right to work).

2. Original documents (British and Irish workers)

  1. See the original document with the person there. A British passport, or an Irish passport or passport card, can be in date or expired. No passport? A UK birth certificate plus an official document with their name and NI number.
  2. Check the photo, the date of birth, and that the document looks real.
  3. Make a copy that cannot be changed.
  4. Record the date: "The date on which this right to work check was made: [date]".

3. A registered digital checking provider (RtW DVSP)

For British and Irish passports, a registered provider can do the check online. It must be on the official register. Except for these registered providers, you cannot rely on a check done by an outside firm such as an agency or adviser (Employer's guide, Annex C).

If they cannot show their status

If they are waiting for a Home Office decision, use Use the Employer Checking Service. You need a "Positive Verification Notice" before they start. It lasts 6 months.

Follow-up checks

If a worker's right to work has an end date, check again on or before that date. British and Irish citizens never need a follow-up. People with EU settled or pre-settled status only need the first check (Right to work checks: an employer's guide (1 October 2026)).

What record to keep

  • A copy of each document, or the online profile page, with the date of the check.
  • Keep it for as long as they work for you, plus 2 years. Then destroy it securely (Checking a job applicant's right to work).
  • In a contract chain: the written statement, the contract, proof of ID checks and any audits.

Do not discriminate

Check everyone the same way. Do not only check people you think are not British, and do not refuse someone because of their accent or name. It can be unlawful discrimination (Right to work checks: an employer's guide (1 October 2026)).

What if you get it wrong?

A civil penalty starts at £45,000 per worker for a first breach, or £60,000 for a repeat. It can be cut by £5,000 for reporting and by £5,000 for helping the Home Office. Use our fine calculator (Code of practice, section 5).

To report a suspicion of illegal working, call the Home Office employers' line on 0300 790 6268 and ask for a reference number (Code of practice).

Want us to handle it?

Sovereign Plus runs CIS payroll for construction firms. Let us check your gang's right to work as part of payroll, keep the records, and remind you before follow-up checks are due.

One thing to know: Home Office guidance says a check only protects you if you do it, someone working under your control does it, or it is done through a registered digital checking provider (an RtW DVSP). Ask us how we set this up for your firm.

Ask about right to work checks   or call 023 9280 0686

Sources

Last checked against GOV.UK: .