A Certificate of Sponsorship (CoS) is an electronic record issued by a UK employer with a valid Sponsor Licence, allowing a migrant worker to apply for a Skilled Worker Visa.
It is one of the most important requirements of the UK work visa system.
The CoS confirms that the employer has offered a genuine job that meets the requirements of the Immigration Rules.
Without a valid Certificate of Sponsorship, a Skilled Worker visa application cannot be submitted.
This guide explains:
• what a Certificate of Sponsorship is
• the difference between defined and undefined CoS
• how employers assign a CoS
• the information contained in a CoS
• common mistakes employers make
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A Certificate of Sponsorship (CoS) is a digital record issued through the Home Office Sponsor Management System (SMS) by a UK employer with a valid sponsor licence.
It confirms that the employer is sponsoring a migrant worker for a specific job role that meets the requirements of the Skilled Worker route.
The CoS contains detailed information about:
Each certificate contains a unique reference number, which the worker must include when submitting their visa application.
A Certificate of Sponsorship is required when a migrant worker applies for most sponsored UK work visas, including the Skilled Worker Visa.
Employers must issue a CoS before the visa application can be submitted.
The CoS confirms to the Home Office that:
There are two types of Certificate of Sponsorship, depending on where the worker is applying from.
A Defined Certificate of Sponsorship is required when a worker applies for a Skilled Worker visa from outside the United Kingdom.
Employers must request a defined CoS through the Sponsor Management System.
The Home Office then reviews the request to confirm that the job meets the Skilled Worker requirements.
Once approved, the employer can assign the certificate to the worker.
An Undefined Certificate of Sponsorship is used when the worker applies from inside the UK.
This commonly includes workers who are:
Undefined CoS allocations are usually granted annually to licensed sponsors.
A Certificate of Sponsorship includes several important pieces of information that the Home Office will use when assessing the visa application.
This includes:
Incorrect information in the CoS can lead to visa refusal.
Employers should ensure the details accurately reflect the employment being offered.
To assign a Certificate of Sponsorship, an employer must:
The role must also appear on the list of eligible occupations under the Skilled Worker route.
Employers assign Certificates of Sponsorship using the Sponsor Management System (SMS).
The process typically involves:
confirming the job details and occupation code
confirming the salary meets immigration requirements
entering the worker’s personal details
paying the CoS assignment fee
assigning the certificate to the worker
Once assigned, the worker receives the CoS reference number, which is required when submitting the visa application.
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Once assigned, a Certificate of Sponsorship is normally valid for three months.
The worker must submit their visa application before the certificate expires.
If the visa application is not submitted within this period, the employer may need to issue a new certificate.
Employers may need to pay several fees when sponsoring migrant workers.
These may include:
The Immigration Skills Charge varies depending on the size of the business and the length of employment.
Employers sponsoring migrant workers must comply with strict Home Office sponsor duties.
These duties include:
Failure to comply with these duties can lead to serious consequences, including:
Workers sponsored under the Skilled Worker route may eventually qualify for Indefinite Leave to Remain (ILR) after completing five years of continuous residence.
The Certificate of Sponsorship forms part of the immigration record used during the visa period.
Correctly assigning a Certificate of Sponsorship is critical to avoiding visa refusals and compliance problems.
At First Migration, we assist employers with:
A Certificate of Sponsorship is an electronic record issued by a UK employer with a sponsor licence that allows a migrant worker to apply for a Skilled Worker visa.
No. A Certificate of Sponsorship is not a physical document. It is a digital record issued through the Home Office Sponsor Management System.
A Certificate of Sponsorship is normally valid for three months from the date it is assigned. The visa application must be submitted within this period.
A Defined CoS is used when a worker applies for a Skilled Worker visa from outside the UK, while an Undefined CoS is used when the worker applies from within the UK.
The Certificate of Sponsorship is assigned by the sponsoring employer through the Home Office Sponsor Management System (SMS).
Yes. If the information in the Certificate of Sponsorship is incorrect or inconsistent with the visa application, the Home Office may refuse the visa.
No. A Certificate of Sponsorship allows the worker to apply for a visa, but the final decision is made by the Home Office.
Yes. An employer may withdraw a Certificate of Sponsorship if circumstances change before the visa decision is made.
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