Immigration Due Diligence for M&A in the UK: What Buyers and Sellers Must Check in 2026

Immigration due diligence m&a uk has moved from a peripheral workstream to a transaction-critical exercise in 2026. Following a series of immigration reforms and successive increases in sponsor and skilled-worker requirements introduced through 2024 and 2025, sponsor compliance obligations and employer liabilities have expanded materially, meaning that unremediated immigration defects can now translate directly into civil penalties, operational disruption and reduced consideration. Buyers who fail to interrogate a target’s sponsor licence, right-to-work records and sponsored-worker files risk inheriting exposure they cannot easily fix; sellers who ignore latent defects risk price chips, escrows and stalled completions.

This practical playbook translates the current regulatory framework into a concrete due-diligence checklist, sample SPA drafting points, a seller remediation plan and a 30/60/90-day post-completion programme.

Quick legal overview and controlling authorities

Immigration due diligence m&a uk rests on a small number of controlling legal instruments. UK immigration control derives from the Immigration Act 1971, which provides part of the statutory framework for who may enter and work in the United Kingdom. The civil penalty regime for illegal working has its statutory basis in the Immigration, Asylum and Nationality Act 2006 (as amended), and the Immigration Act 2016 further strengthened enforcement powers and the consequences of illegal working. Employers who engage workers without a valid right to work face civil penalties, and the Home Office publishes its enforcement approach in its illegal working enforcement collection.

Two operational duties dominate any acquisition. First, employers must carry out and evidence right-to-work checks; a correctly conducted check establishes a statutory excuse against a civil penalty, and a deficient check loses that protection, as set out in the Home Office guidance on how to check a job applicant’s right to work in the UK. Second, any business employing sponsored migrant workers must hold and maintain a sponsor licence and comply with the duties described in the guidance on how to apply for a sponsor licence.

Key statutes and guidance

• Immigration Act 1971. Primary statutory basis for UK immigration control and employer obligations.
• Immigration, Asylum and Nationality Act 2006 and Immigration Act 2016. Civil penalties, enforcement powers and compliance provisions relevant to liability allocation.
• Home Office sponsor guidance. Sponsor licence duties, key personnel roles and record-keeping expectations, set out in the published Workers and Temporary Workers sponsor guidance.
• Right-to-work guidance. Permitted documents, online checks and the statutory excuse regime, set out in the Home Office employer’s right-to-work checks guidance.
• ICO employment guidance. Lawful handling and retention of immigration and personnel data under data-protection law, per the ICO guidance on employment and worker data.

How immigration risk arises in M&A, share versus asset deals

The single most important structural question in immigration due diligence m&a uk is whether the transaction is a share purchase or an asset purchase, because the deal structure determines whether, and how, immigration liabilities move to the buyer. The mechanics differ sharply, and the wrong assumption can leave a buyer with unfunded exposure or a workforce whose legal basis to work has evaporated on completion.

Share purchase, typical liabilities

In a share purchase the buyer acquires the company itself, together with all its assets, contracts and liabilities. Historic immigration liabilities generally remain within the target because the legal entity is unchanged; the company simply has new owners. That continuity is a double-edged sword. On one hand, the target’s sponsor licence remains in place, subject to the requirement to report a change of ownership. On the other hand, the buyer inherits every latent defect, historic illegal-working exposure, unreported changes, deficient right-to-work files and any dormant Home Office concern, because those liabilities travel with the entity.

Importantly, where there is a change of control of the sponsor, the licence must be reported to the Home Office through the Sponsor Management System, generally within 20 working days, and a fresh licence application or reassessment may be required. This is why buyers of share targets must scrutinise historic compliance, not merely current status.

Asset purchase, typical liabilities

In an asset purchase the buyer acquires specified assets and, typically, assumes only the liabilities it expressly agrees to take. Liabilities generally remain with the seller unless contractually transferred. The complication is people: where employees transfer under the Transfer of Undertakings (Protection of Employment) Regulations 2006, employment relationships move to the buyer by operation of law. Sponsored workers present a particular hazard because a sponsor licence is not transferable. If the acquiring entity does not hold an appropriate sponsor licence, or fails to apply for one within the required period following the transfer, sponsored employees may lose the legal basis on which they were working, creating urgent operational and compliance risk on day one.

Careful sequencing and pre-completion licence applications are essential.

Buyer due diligence for immigration due diligence m&a uk: what to check

The core of any immigration due diligence m&a uk exercise is a disciplined, document-driven review. The objective is not merely to confirm that a licence exists, but to test whether the target has genuinely discharged its ongoing duties, whether its right-to-work files establish statutory excuses, and whether its records would survive a Home Office compliance visit. The checklist below is structured by workstream, with document requests, a sampling approach and the red flags that should escalate scrutiny.

Sponsor licence due diligence

Sponsor licence due diligence begins with confirming that the licence is current, unexpired and covers the routes on which the target sponsors workers. Request the licence documentation and confirm the identity and continuing employment of the key personnel, the Authorising Officer, Key Contact and Level 1 and Level 2 users, because the Home Office sponsor guidance requires these roles to be properly appointed and maintained.

• Documents to request. Sponsor licence details and rating history; Sponsor Management System user list; certificate of sponsorship allocation and usage; any Home Office correspondence, action plans, downgrades, suspensions or civil penalty notices.
• Online checks. Confirm the entity appears on the Home Office register of licensed sponsors and that its licence status is unqualified.
• Red flags. Vacant key personnel roles, an expired or suspended licence, unexplained CoS shortfalls, or any history of suspension or compliance action.

Right-to-work checks in M&A: sampling, history and evidence

Right to work checks M&A review is where hidden civil-penalty exposure most often surfaces. A valid check establishes a statutory excuse; a defective one does not. Because a full file-by-file review is rarely proportionate, adopt a risk-based sampling approach, weighting the sample towards higher-risk cohorts, recent hires, sponsored workers, agency-supplied staff and any population where documentation is known to be inconsistent.

• Documents to request. Right-to-work check evidence for a representative sample, including retained copies, online-check profiles and the date the check was performed.
• Historic audit trail. Confirm checks were completed before employment began and were repeated where time-limited permission required a follow-up check.
• Sample testing. Increase the sample size where the initial sample reveals gaps; a high defect rate in the sample implies a wider systemic problem.
• Red flags. Missing or undated checks, checks performed after the start date, reliance on unacceptable documents, or an absence of follow-up checks for time-limited leave, each risks loss of the statutory excuse under the right-to-work guidance.

Sponsored workers, CoS and start dates

For each sponsored worker, reconcile the certificate of sponsorship against the actual role, salary, work location and start date. Mismatches between the CoS particulars and the real employment relationship are a common compliance failure and a frequent trigger for Home Office action.

• Reconcile. CoS details against employment contracts, payroll, actual duties and reporting lines.
• Check reporting. Confirm that reportable events, changes to salary, role, location or start date, and significant absences, were reported through the Sponsor Management System within the required timeframes.
• Red flags. Salaries below the relevant going rate or general threshold, undisclosed role changes, or sponsored workers no longer performing the sponsored role.

Immigration records and HR systems

Effective immigration due diligence m&a uk also tests the systems that generate compliance, not just the outputs. Poor record-keeping is itself a breach of sponsor duties and a strong predictor of substantive defects. Assess how the target names, stores and retains right-to-work and sponsorship records, and confirm that retention practices align with the ICO guidance on employment and worker data so that records are both compliant and lawfully retained.

• Review. File-naming conventions, document retention schedules, and the location and accessibility of immigration records.
• Assess. Whether HR and payroll systems flag visa expiry dates and trigger follow-up checks automatically.
• Red flags. Fragmented records, no central register of sponsored workers, or retention practices that either destroy records too early or hold them without a lawful basis.

Third-party contractors and agency workers

Illegal-working exposure is not confined to direct employees. Where the target relies on agency workers or contractors, confirm who bears responsibility for right-to-work checks and whether the contractual arrangements are consistent with the way the individuals actually work. Misclassified contractors who are in reality workers of the target can generate civil-penalty exposure under the illegal working enforcement regime.

• Request. Agency and contractor agreements, indemnities relating to right-to-work compliance, and evidence of checks where the target is the responsible party.
• Red flags. Absence of contractual allocation of right-to-work responsibility, or long-term “contractors” integrated into the target’s workforce without checks.

Download the Immigration Due Diligence Checklist to run this review consistently across every workstream in your next transaction.

Seller remediation before completion, practical steps and timelines

A well-advised seller does not wait for the buyer to discover defects. Proactive remediation preserves value, narrows the scope of indemnities and reduces the risk of a price chip or aborted deal. The most defensible position for a seller in an immigration due diligence m&a uk process is to have identified issues, fixed what can be fixed, and disclosed the residue transparently in the data room with supporting evidence.

Sponsor licence fixes

Where sponsor duties have slipped, act early. Appoint or replace key personnel so that the Authorising Officer, Key Contact and Level 1 and Level 2 users are current and correctly recorded, as the Home Office sponsor guidance requires. Deliver compliance training to those with Sponsor Management System responsibilities, correct any inaccurate records, and lodge overdue notifications through the SMS. Because licence corrections and personnel changes take time to process, sellers should treat this as a 30 to 60-day workstream rather than a completion-eve fix.

Right-to-work remediation and retrospective checks

Where the sampling exercise reveals gaps, the seller should conduct retrospective right-to-work checks for the affected population and document them. A retrospective check cannot fully cure a historic failure, the statutory excuse depends on the check being carried out at the correct time, but it confirms current legal status, limits ongoing exposure and demonstrates good faith. Follow the acceptable-document and online-check requirements in the right-to-work guidance, and retain the resulting evidence in a manner consistent with data-protection obligations.

Evidence of remediation for disclosure schedules

Remediation only reduces contractual risk if it is evidenced. Assemble a remediation dossier for the disclosure schedule: dated records of retrospective checks, confirmations of SMS notifications, training completion records, and correspondence with UK Visas and Immigration. Transparent disclosure, backed by evidence, is the seller’s strongest defence against a later warranty claim, because a properly disclosed matter is generally carved out of the warranties it qualifies.

Contractual protections: immigration warranties, indemnities and escrows

Even after diligence and remediation, residual immigration risk almost always remains, some defects are historic and incurable, and some exposures crystallise only if the Home Office acts. Contractual protection allocates that residual risk. Well-drafted immigration warranties SPA provisions, a targeted indemnity and, where appropriate, an escrow or holdback, convert diffuse regulatory risk into a defined commercial allocation between the parties.

Warranties versus indemnities versus escrow solutions

Warranties are contractual statements about the state of the target; a breach gives rise to a damages claim measured by the reduction in value, subject to the buyer proving loss and mitigating. A specific indemnity, by contrast, provides a pound-for-pound recovery for a defined risk without the buyer having to prove loss of value, the preferred mechanism for a quantifiable, identified exposure such as a known right-to-work gap. Where the potential liability is quantifiable and time-limited, an escrow or holdback sets funds aside to meet the cost of remediation or penalties, giving the buyer certainty of recovery. The right combination depends on whether the risk is general (favouring warranties) or specific and known (favouring an indemnity, often supported by escrow).

Draft clause, seller warranty (example)

The following plain-text example is illustrative only and is not legal advice; any clause must be tailored to the transaction and the disclosed position.

“The Company holds a valid sponsor licence, has complied in all material respects with its sponsor duties and with all applicable right-to-work check obligations, has conducted and retained right-to-work checks for each employee sufficient to establish a statutory excuse, and has received no civil penalty notice, licence suspension, downgrade or revocation, nor any notification of any investigation or compliance action, in each case save as fairly disclosed in the Disclosure Letter.”

Draft clause, indemnity and survival considerations

“The Seller shall indemnify the Buyer against all losses, civil penalties, professional fees and remediation costs arising from any failure prior to Completion to conduct or retain a compliant right-to-work check, or from any breach of sponsor duties, whether or not disclosed, up to [cap] and for a period of [survival period] from Completion.”

Negotiation points include the indemnity cap (immigration indemnities are often carved out of the general warranty cap and treated like a fundamental or tax-style indemnity), the survival period (which should reflect the enforcement horizon rather than a short general limitation), and the disclosure scope (a buyer will resist “whether or not disclosed” wording for general warranties but may accept it for a specific indemnity covering an identified risk).

Post-completion remediation and compliance plan (30/60/90)

Contractual protection does not restore compliance, the buyer must stabilise the acquired workforce operationally. A structured 30/60/90-day plan converts post-completion immigration remediation from a reactive scramble into a governed programme with owners, deliverables and KPIs. The plan below assumes a share acquisition where the target’s sponsor licence and sponsored workforce continue, subject to reporting any change of control; asset deals require earlier action to secure a licence before or promptly after completion.

Immediate (days 0–30)

• Appoint a named compliance lead and confirm the key personnel remain correctly recorded on the Sponsor Management System; report any change of ownership or control to the Home Office within the required period.
• Commission a full sponsor and right-to-work audit, prioritising any populations flagged during diligence.
• Carry out right-to-work re-checks where diligence identified gaps, and document each check.
• Implement immediate corrective actions and log all remediation with dated evidence.

Medium term (days 31–60)

• Integrate the target’s immigration records and HR systems into the buyer’s compliance framework, including visa-expiry monitoring.
• Deliver sponsor compliance training to all users with Sponsor Management System responsibilities.
• Close out reporting gaps by lodging any outstanding notifications with UK Visas and Immigration.

Longer term (days 61–90)

• Report on KPIs: percentage of files with a valid statutory excuse, notifications filed on time, and outstanding corrective actions closed.
• Run a mock compliance visit to test readiness for a Home Office audit.
• Finalise the integrated compliance policy and confirm ownership of ongoing sponsor duties.

Risk matrix and commercial negotiation checklist

A risk matrix translates diligence findings into commercial outcomes, mapping each category of UK sponsor licence risk to the buyer’s likely remedy. This helps counsel prioritise negotiation and identify where warranty and indemnity insurance may be available to bridge residual exposure.

When immigration risk justifies walk-away

Most immigration risk is priceable and manageable. Walk-away is reserved for cases where the exposure is both material and uncontainable, for example, a live licence revocation risk that would deprive the buyer of a substantial sponsored workforce, or evidence of systemic illegal working that no indemnity could realistically cap. In those cases, the operational disruption and reputational exposure may outweigh the strategic rationale for the deal.

Comparison table, share sale versus asset sale: immigration consequences

The table below summarises the practical differences that drive immigration due diligence m&a uk strategy across the two deal structures.

When to instruct specialist immigration counsel

Specialist counsel adds most value early, when structure and diligence scope are still open. Instruct immigration counsel where the target sponsors workers, where diligence reveals right-to-work or sponsor-licence defects, where the deal is an asset purchase involving sponsored staff, or where the SPA requires bespoke immigration warranties and indemnities. Counsel supports the transaction by scoping the diligence sample, interpreting Home Office correspondence, drafting and negotiating the immigration provisions of the SPA, designing the remediation plan and, in asset deals, sequencing a pre-completion sponsor licence application so that the workforce remains lawfully employed from day one.

Key documents to request in a data room

• Sponsor licence details, rating history and Sponsor Management System user list.
• Certificate of sponsorship allocation and usage records.
• Right-to-work check evidence for a representative employee sample.
• Register of sponsored workers with role, salary, location and start date.
• All Home Office and UK Visas and Immigration correspondence, action plans and any penalty notices.
• Immigration compliance policies, training records and record-retention schedules.
• Agency and contractor agreements addressing right-to-work responsibility.

Practical cost and time estimates for remediation

Cost and time depend heavily on the scale of the defect and are indicative only. Sponsor licence corrections and key-personnel changes are generally processed within a matter of weeks, though timelines vary and any expedited or priority services offered by the Home Office attract additional fees at the rates then in force. Retrospective right-to-work check programmes are usually costed by headcount and internal HR time rather than external fees.

Where the risk is a potential civil penalty, note that penalties are set by the Home Office per illegal worker at the current published maximum, and budget against the enforcement outcomes described in the Home Office illegal working enforcement collection; treat any figure as a working estimate to be confirmed against the specific facts and current rates. Larger remediation programmes benefit from a dedicated project owner and a documented budget aligned to the 30/60/90-day plan.

Conclusion

Immigration due diligence m&a uk is now an unavoidable component of any UK transaction involving a sponsored or migrant workforce, and the recent tightening of the sponsor-compliance regime has raised the stakes for buyers and sellers alike. Buyers should run a structured, sampling-based verification of the sponsor licence, right-to-work files and sponsored-worker records; sellers should remediate early and disclose transparently; and both should allocate residual risk through tailored warranties, indemnities and, where appropriate, escrow. A disciplined 30/60/90-day post-completion plan then converts contractual protection into operational compliance. Download the Immigration Due Diligence Checklist and sample SPA clauses to apply this playbook to your next deal.

Sources

1. UK Government, Sponsor a worker: apply for a sponsor licence
2. UK Government, Check a job applicant’s right to work in the UK
3. Legislation.gov.uk, Immigration Act 1971
4. Legislation.gov.uk, Immigration Act 2016
5. UK Government, Illegal working enforcement
6. Information Commissioner’s Office, Employment and worker data
7. The Law Society
8. UK Visas and Immigration