Reporting Illegal Immigrants (Employer Advice)


What should you do if you establish your business has been employing an illegal worker? What is the process for reporting illegal immigrants?

It is a legal requirement on all UK employers to carry out prescribed document checks on their employees and prospective employees to verify their right to work in the UK. The checks must be carried out prior to each individual starting their employment with you, and at regular intervals should the individual hold temporary permission to work.

Where a right to work check reveals that an employee is not eligible to work in the UK, or you are otherwise made aware of this fact, and you continue to employ the individual, you may become liable for a civil penalty of up to £20,000 per breach and potentially criminal prosecution. Many employers will consider instant dismissal of the illegal immigrant as the obvious course of action, but this can give rise to other issues such as discrimination claims if not handled through fair and reasonable process. As such, your next step should demand careful consideration on the basis of professional legal advice.

What do you do if you believe you are employing an illegal worker, and what is required of you in terms of reporting illegal immigrants?

Employers reporting illegal immigrants

It is a criminal offence to undertake work at a time when that person knows, or has reasonable cause to believe, that they are disqualified from working by reason of their immigration status.

You can report illegal immigrants on the Home Office website or by calling the Immigration Enforcement hotline on 0300 123 7000. While you can do so anonymously and in confidence, it is also possible to provide your business details; this may be of benefit in demonstrating your commitment to immigration compliance during any subsequent UKVI investigation into illegal working at your organisation.

Whilst you are not duty bound to report an illegal immigrant to the Home Office, you should consider the impact on your Home Office compliance and reputation should the illegal worker come to the Home Office’s attention via another source of intelligence, such as an anonymous tip-off.


How to identify illegal immigrants

Employers should have in place company processes to prevent and identify any form of illegal working, thereby meeting their right to work duties.

Prospective employees

Your recruitment and onboarding of new employees must include provision to carry out effective right to work checks. Assumptions should never be made as to an individual’s entitlement to work, regardless of their race, ethnicity or nationality. As such, right to work checks should be carried out on all prospective employees, including British nationals.

Make it clear as part of your recruitment process that all potential employees will be required to present valid documentation to evidence their permission to carry out the type of work on offer in the UK. This can help to act as a deterrent to potential illegal workers.

When carrying out a right to work check your employee will need to provide you with an original document, or combination of documents, from the relevant Home Office approved list. You will need to carefully check the validity of that documentation and retain a clear copy. You will also need to make a contemporaneous record of the date on which you conducted your check.

When checking the validity of documentation presented to you by a prospective or existing employee, you must ensure that:

  • the documentation is genuine, original and has not been tampered with.
  • the person presenting the documentation is the rightful holder.
  • the photographs and dates of birth are consistent across multiple documents and with the individual’s appearance.
  • the expiry dates for permission to be in the UK have not passed and any work restrictions still permit the type of work, including any limit on the number of hours the individual is allowed to work.
  • there is an explanation for any difference in names across multiple documents. You should seek further documentation to explain any differences, eg, an original marriage certificate or divorce decree. Any further documents must also be copied and retained.


You are not expected to be an expert in identifying fraudulent documentation. If you are provided with a false document you will only face a civil penalty if it is ‘reasonably apparent’ that it is not genuine or does not belong to the holder.

When an employee or applicant is not able to present valid or relevant right to work documents, the government’s Employer Checking Service can be used by employers to confirm the individual’s immigration status. Note that the individual must give permission for you to use this service.

Existing employees

For existing employees who have presented relevant documents from List A no further checks are required. Those employees however with time-limited or restricted permission to work in the UK, will require repeat checks to confirm that any permission has not expired during the course of their employment, rendering you non-compliant in your duties.

In these circumstances, it isn’t uncommon for the employer to become aware that the employee has lost their right to work. This could be for a number of reasons, such as visa expiry or revocation, and it will be important for the employer to understand why the employee no longer has permission before considering their next move.

If you are already employing a migrant worker, and they no longer have permission to be in the UK or undertake the work on offer, you should seek legal advice immediately. By continuing to employ an illegal worker, you risk significant consequences for both you and your business. This includes tough civil and criminal sanctions, as well as potential disruption to your business and serious reputational damage.

Even where you have undertaken the correct right to work checks, you may still be liable where you knew or it was reasonably apparent that the documentation checked was not genuine, did not rightfully belong to the holder or the work was not as permitted under their visa conditions.

In these circumstances, you will be unable to establish a ‘statutory excuse’ to defend against Home Office penalties. In addition to the civil and criminal sanctions that my be imposed for employing illegal immigrants, you may suffer significant disruption to your business by way of loss of staff, as well as serious reputational damage to your business. Any employer penalised by the Home Office will be identified in their illegal working penalties publication.

Need assistance?

By correctly carrying out right to work checks, and where necessary rechecking an employee’s status, you will be able to establish and retain a statutory excuse in the event that you are facing allegations of employing illegal immigrants.

If you identify employees who are not eligible to work in the UK, either through right to work checks or otherwise, you will need to take action to ensure you are not in breach of your prevention of illegal working duties.

You should also consider your options for reporting illegal immigrants to the relevant authorities. By reporting illegal immigrants you are preventing those workers from gaining or keeping employment with other employers, who in turn may then become liable to both civil and criminal penalties.

DavidsonMorris specialise in helping employers with Home Office allegations of illegal immigration and advising on measures required to ensure compliance with your right to work duties. Contact us for legal advice from our experienced immigration specialists to help you avoid the procedural pitfalls when employing migrant workers, ensuring that you remain compliant.


Founder and Managing Director Anne Morris is a fully qualified solicitor and trusted adviser to large corporates through to SMEs, providing strategic immigration and global mobility advice to support employers with UK operations to meet their workforce needs through corporate immigration.

She is a recognised by Legal 500 and Chambers as a legal expert and delivers Board-level advice on business migration and compliance risk management as well as overseeing the firm’s development of new client propositions and delivery of cost and time efficient processing of applications.

Anne is an active public speaker, immigration commentator, and immigration policy contributor and regularly hosts training sessions for employers and HR professionals

About DavidsonMorris

As employer solutions lawyers, DavidsonMorris offers a complete and cost-effective capability to meet employers’ needs across UK immigration and employment law, HR and global mobility.

Led by Anne Morris, one of the UK’s preeminent immigration lawyers, and with rankings in The Legal 500 and Chambers & Partners, we’re a multi-disciplinary team helping organisations to meet their people objectives, while reducing legal risk and nurturing workforce relations.

Legal Disclaimer

The matters contained in this article are intended to be for general information purposes only. This article does not constitute legal advice, nor is it a complete or authoritative statement of the law, and should not be treated as such. Whilst every effort is made to ensure that the information is correct at the time of writing, no warranty, express or implied, is given as to its accuracy and no liability is accepted for any error or omission. Before acting on any of the information contained herein, expert legal advice should be sought.

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