How to Check if a CoS Is Genuine

Synopsis

Always verify your employer on the Home Office Register of Licensed Sponsors before using a CoS for your visa application.
A genuine CoS number is exactly 11 characters and always begins with the letter "C".
Only a CoS with "Assigned" status in the SMS is valid for a UK visa application.
Missing PAYE details, incorrect SOC codes, or salary below UKVI thresholds are common signs of a fake or poorly issued CoS.
If fraud is suspected, do not submit visa application, report it to the Home Office and seek regulated immigration advice.

What Is a Home Office Certificate of Sponsorship?

A Certificate of Sponsorship (CoS) is a digital record issued by a UK-licensed employer through the Home Office Sponsor Management System (SMS). It is not a physical certificate, it exists only as an electronic entry assigned to a specific worker.

The CoS contains employee's job title, SOC code, salary, start and end dates, and personal details. It carries an 11-character reference number beginning with "C" that was enter when applying for a UK Skilled Worker visa or another sponsored work route.

Why It's Important to Verify a CoS Is Genuine

Employers play a critical role in ensuring that Certificate of Sponsorship (CoS) records are accurate, valid, and issued through the correct Home Office processes. Fraudulent sponsorship schemes and fabricated CoS details can expose both workers and organisations to serious immigration and compliance risks.

A worker who relies on a fraudulent or invalid CoS may face:

Visa refusal or cancellation.
Potential immigration enforcement action.
Restrictions on future UK immigration applications.
Long-term damage to their employment and immigration record.

Even where fraud is not involved, inaccuracies in the CoS such as an incorrect salary, SOC code, job title, or personal details can result in a visa refusal and unnecessary delays.

1. Verify the Sponsor Licence

Your first step is to confirm your employer holds an active UK sponsor licence. Search for them by name on the official Home Office Register of Licensed Sponsors.

Check that the business name and address match what's on your offer letter, and that the licence type covers Skilled Worker sponsorship. If the employer is absent from the register, or their licence shows as suspended or revoked, do not proceed with the application.

2. Check the CoS Number Format

A valid CoS number is exactly 11 characters long and always starts with the letter "C" for example, C12345678901. If the reference you've received is too short, too long, or formatted differently, treat this as a red flag and request clarification from your employer directly.

3. Confirm Assignment and Expiry Dates

Every CoS has an assignment date and an expiry date. A Defined CoS (for applicants outside the UK) must be used within 3 months of assignment. If the expiry date has already passed, or the dates don't align with your agreed employment start date, the CoS cannot be used. Request a corrected or newly assigned CoS from your employer.

4. Cross-Check Job Details

Employers should ensure that the details recorded on the Certificate of Sponsorship (CoS) accurately reflect the terms offered to the worker before the visa application is submitted. Key information to verify includes:

Job title : Should match the position stated in the employment contract or offer letter.
SOC code : Must correspond to the role being sponsored and align with the appropriate occupation code under the UK Skilled Worker route.
Salary : Must meet the applicable salary threshold and going rate requirements for the selected SOC code, check using the CoS document checklist

Any discrepancies between the CoS record and the agreed employment terms should be corrected before the worker applies for their visa. Inaccurate sponsorship details can lead to processing delays, requests for further information, or visa refusal.

5. Review Personal Information

Employers should ensure that all personal details recorded on the Certificate of Sponsorship (CoS) match the worker’s passport exactly. This includes

Worker’s full legal name
Passport number
Date of birth
Nationality

Even minor discrepancies, such as spelling errors, missing middle names, or incorrect passport details, can create issues during visa processing. Before the worker submits their application, employers should verify that all information in the Sponsor Management System (SMS) aligns with the passport and supporting documentation.

If any inaccuracies are identified, the CoS record should be corrected promptly through the SMS to avoid application delays, requests for additional information, or potential visa refusal.

6. Check CoS Status

A CoS can exist in multiple states within the SMS. Only one status allows you to apply for a visa:

CoS Status Reference

Status	Meaning	Can You Apply?
Created	Drafted but not yet assigned to a worker	No
Assigned	Officially issued and ready for visa use	Yes
Used	Already used in a previous visa application	No
Withdrawn / Cancelled	No longer valid	No

Before the employee submits their visa application, employers should confirm the Certificate of Sponsorship (CoS) status directly within the Sponsor Management System (SMS). Only a CoS with an “Assigned” status can be used to support a UK Skilled Worker visa application.

Verifying the CoS status before submission helps ensure that the sponsorship record is active, valid, and ready for use, reducing the risk of application delays or processing issues.

7. Look for Missing Key Details

A genuine CoS will always include a PAYE reference number, a valid SOC code, a salary that meets UKVI thresholds, and accurate employment dates. Common warning signs of a fake or poorly issued CoS include:

No PAYE reference listed
Missing or incorrect SOC code
Salary below the minimum going rate or incorrectly marked as "new entrant"
References to discontinued policies (e.g. shortage occupation discounts removed in 2024)

8. Provide Clear CoS Verification Support to Sponsored Workers

Employers should ensure that sponsored workers have a clear point of contact within the HR, mobility, or immigration team for any sponsorship-related queries. Providing accurate and timely information helps workers verify their visa application details and avoid unnecessary delays.

Where requested, employers should be prepared to confirm key Certificate of Sponsorship (CoS) information, including:

The CoS reference number.
The assignment date recorded in the Sponsor Management System (SMS).
The current CoS status.
Confirmation that the CoS has not previously been used in a visa application.

Transparent communication and prompt verification of sponsorship details help maintain confidence in the sponsorship process and support a smoother visa application experience for the worker.

9. Still in Doubt? Get Help from Jobbatical

f there is any uncertainty regarding a worker’s sponsorship record or Certificate of Sponsorship (CoS) details, employers should seek guidance from a qualified immigration professional before the visa application is submitted. Early verification can help identify discrepancies, prevent processing delays, and reduce the risk of costly errors.

You can also report suspected immigration fraud to the Home Office at gov.uk/report-immigration-crime.

Disclaimer: Immigration rules change quite frequently; please verify with official sources or contact us for the latest info before making any decisions.