How to verify your UK employer is a real, licensed sponsor before you pay anything

The most important thing to understand about CoS fraud is that the employer — not the document — is the primary target for verification. A forged CoS can look perfect. But a fraudulent employer will always fail one or more of the following checks. Do them in order. Stop the moment one fails.

Step 1: UKVI Register of Licensed Sponsors.

Go to the official UK government website and search for "Register of Licensed Sponsors." Download the list (it is a spreadsheet) or use the online search tool. Search for your employer's name. If they do not appear, they are not licensed to issue a Certificate of Sponsorship. Full stop. Do not proceed. Do not pay anything.

If they do appear, note the licence type (Worker, Student, or both) and the rating (A-rated or B-rated). A B-rating means the sponsor is under a performance improvement plan and may have restrictions on how many CoS certificates they can issue. This does not make the CoS fake, but it is worth noting.

Step 2: Companies House.

Go to find-and-update.company-information.service.gov.uk and search for the employer. Verify: the registration number on the CoS matches the Companies House record; the company status is "Active" (not dissolved or in administration); the registered address is consistent with what you have been told; and the company was incorporated long enough ago to be plausible as an established employer.

A company incorporated in the last six months that claims to be a large care home group is suspicious. A company with no filed accounts is suspicious. Neither of these facts alone proves fraud, but both are risk factors.

Step 3: Call the company directly — using a number you find yourself.

Do not call any phone number provided by the recruiter or in the CoS document. Instead, find the company's main telephone number through their official website (search for it independently), through Companies House, or through directory listings. Call them. Ask to speak to HR. Ask them to confirm that they have issued a Certificate of Sponsorship in your name for the role you have been offered.

This one check defeats virtually every impersonation fraud. A genuine NHS Trust, care home group, or tech company has an HR department. They will confirm or deny the placement. If the switchboard has no record of you, walk away.

Step 4: Verify the CoS reference number format.

A genuine CoS reference number is eleven alphanumeric characters. The specific format is not published by UKVI — but SponsorShield can flag structural inconsistencies in reference numbers that do not match the expected pattern. If your reference number is nine characters, fourteen characters, or uses a format inconsistent with genuine CoS references, this is a significant red flag.

Step 5: Check the document metadata.

If you know how, open your CoS PDF in a tool that can read document properties and check: the creation date (should not predate the sponsorship offer), the creator software (should not be Canva, Word, or similar consumer tools), and whether the document has been edited after creation (a legitimate CoS is generated once, not revised).

SponsorShield runs all of these checks automatically as part of the CoreFlux™ risk analysis. You do not need to know how to read PDF metadata — upload the document and the report will flag any anomalies.

If your employer is legitimate, none of these checks will cause any problem. A real sponsor will be on the UKVI register, will have a normal Companies House record, and will be able to confirm your employment by phone. Only fraudulent employers fail these checks.

1. 1

   Never pay any fee described as a sponsor fee, CoS fee, security bond, or processing charge.

   These are illegal under UKVI guidance. Licensed sponsors pay the costs of sponsorship. Workers do not.

2. 2

   Never accept a CoS via WhatsApp or personal email only.

   Genuine sponsorship comes through a formal employment process. If there is no formal contract, no HR contact, and no verifiable company, stop.

3. 3

   Never submit a visa application based on a CoS you have not verified.

   A UKVI visa application costs hundreds of pounds. A fraudulent CoS will result in refusal, a potential ban, and no refund.