Certificate of Sponsorship (CoS)
If you’re a UK-based employer that wishes to recruit an overseas national, you must hold a valid sponsor licence and issue a Certificate of Sponsorship (CoS) to the prospective employee before they can apply for the appropriate work visa.
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What is a Certificate of Sponsorship?
A Certificate of Sponsorship or COS is an electronic certificate that is required to be issued to any migrant worker who intends to submit an application via a relevant worker route.
A Certificate of Sponsorship (CoS) must be applied for by a UK-based employer each time they wish to recruit an overseas national on Skilled Worker Visa (formally known as a Tier 2 Visa) Once the certificate has been obtained, it will be used by your prospective employee as a supporting document for their visa application. Only employers that hold a Sponsor Licence are able to apply for a Certificate of Sponsorship.
The CoS UK application should only be commenced by an employer once the job has been formally offered. As part of the application, an employer should provide details regarding both the role and salary. If there are any differences between the information provided and the reality, the employer will be at risk of having their Sponsor Licence suspended.
There are two types of Certificate of Sponsorship UK currently allocated by the government- Restricted and Unrestricted.
How to Get Certificate of Sponsorship in UK?
To apply for a CoS, an employer must first obtain a Sponsor Licence. This is the central eligibility requirement that must be satisfied in order to obtain a Home Office Certificate of Sponsorship, as the certificate essentially acts as proof that the employee has a job offer from a sponsored employer.
Once your CoS Sponsorship Licence is in place, it is then necessary to ensure that you allocate the correct certificate to your prospective employee.
In order to do this, you must gather all relevant information regarding the role being applied for including the likely salary that will be paid.
Once the information is in place, it needs to be inputted the Sponsor Management System (SMS). The SMS will then produce the CoS in the form of a unique reference number.
This number will be used by your prospective employee as part of their visa application.
Are there specific rules that must be adhered to when applying CoS?
When you apply for a CoS, it is hugely important that the relevant guidelines are followed correctly. For example, your prospective employee must apply for clearance within three months of the CoS being issued.
In addition, the CoS can only be assigned to the individual it was originally applied for. It is not permissible for it to be transferred. If you were to attempt to reassign a CoS to a different individual, it would be viewed as a violation of your duties as a sponsored employer.
This would put your organisation at risk of having your Sponsor Licence revoked or suspended by the Home Office.
In addition, you can also have your Sponsor Licence revoked if it becomes clear that you know longer comply with the ‘Genuineness Test’. The test is the Home Office’s way of determining whether you have a genuine need for overseas workers.
What is the Sponsor Management System (SMS)?
If your application for a Sponsor Licence is successful, one of your key tasks will be to use the Sponsor Management System (SMS) effectively.
The SMS is used to keep a log of all of the overseas workers that you employ. You should use the SMS to record any periods of absence or changes in immigration status. It is also how to make changes to a Certificate of Sponsorship once assigned.
In addition, you should update the system if an employee is not complying with their visa or receives a promotion.
You also use the SMS to obtain a CoS. This is achieved through inputting all relevant information about the role and the prospective employee into the system.
The SMS uses the information provided to produce the correct CoS.
Types of Certificate of Sponsorship
Defined COS
There are defined and undefined COS. Foreign candidates for a Skilled Worker Visa are awarded “defined certificates of sponsorship” (previously “restricted certificates”). After receiving their sponsor licence, companies may then apply for the certificates of sponsorship using the SMS system.
Undefined COS
Skilled worker visa candidates currently in the UK and candidates for other visa categories need undefined COS (formerly known as “unrestricted certificates”) to be hired.
Certificate of Sponsorship (CoS) Processing Time
In most cases, the processing time for a Certificate of Sponsorship takes around one working day to complete. However, this time frame may be extended if the Home Office requests additional clarification of the information that has been submitted.
After being authorised, the certificate will be made available in the employer’s Sponsor Management System (SMS) account, where it will be given to the skilled worker who has been designated. It is necessary for an employer to be in possession of a sponsor licence in order to be able to issue a Certificate of Sponsorship. This licence grants the business permission to lawfully recruit skilled migrant employees once the workers have submitted an application for a visa.
Certificate of Sponsorship Cost
The CoS cost is relative to the type of visa being applied for by your prospective employee.
The cost of obtaining a Certificate of Sponsorship depends on the type of visa being applied for. For a Skilled Worker (except workers on the International Sportsperson visa) the cost is £525 and £55 for a temporary worker.
The Immigration Skills Charge must be paid for Skilled Worker Visa.
How to Assign a Certificate of Sponsorship (CoS)?
The SMS system is a web-based program that enables an employer in the UK to provide a Certificate of Sponsorship to a prospective employee in order to make it possible for the worker to submit an application for a visa to the UK. The process of assigning a Certificate of Sponsorship is now much simpler using the SMS system.
The procedures that must be followed in order to allocate a COS change are based on the particular type of COS that must be assigned. In order to log in to the SMS account of the organisation and attentively follow the instructions, the Level 1 user of the organisation is required to do so before any form of COS may be assigned.
When it comes to issuing the Certificate of Sponsorship, there are a lot of factors to take into consideration. Any mistakes can lead to the worker’s visa application being denied, as well as enforcement action being taken by the Home Office against the employer in the form of a sponsor licence suspension, downgrade, or even revocation. Assigning a COS can be easier with the presence of a lawyer to help you. Call our professional team on 020 4502 8582.
Annual Certificate of Sponsorship Allocation
Estimate the number of Undefined COS You Need for A Year
Because of your annual allocation, there will be a limit on the total number of certifications that may be issued in a given year. The Home Office will ask UK employers to provide an estimate of the number of undefined COS you will require during your first year as a sponsor when you make your first application for a sponsor licence.
As a sponsor licence holder, you will be required to explain the quantity you estimate you will need as part of this procedure. If your request is granted, the number of certificates of sponsorship will be allocated to you for the first year.
CoS Year
The annual COS allocation (COS Year) continues for 12 months from the day your sponsor licence was issued or from the date your most recent renewal application was approved.
When applying for the licence, you will be required to provide an estimate and a request for the number of undefined certificates that you expect to employ throughout the course of the next year.
If You Spend All Your COS Before 12 Months
In the event that your application is accepted, the Home Office will assign the COS to your SMS. These must be utilised within the allotted time frame of one year. If you use up all of the COS that was allocated to you, you have the option to make a request for more.
Sponsors can request an increase in their COS allocation by submitting a request via the SMS system. A reason must be stated when requesting an allocation increase. The result of a request for an in-year allocation increase may take up to 18 weeks unless priority services are requested.
Legal Disclaimer
The information provided is for general informational purposes only and does not constitute legal advice. While we make every effort to ensure accuracy, the law may change, and the information may not reflect the most current legal developments. No warranty is given regarding the accuracy or completeness of the information, and we do not accept liability in such cases. We recommend consulting with a qualified lawyer at London Immigration Lawyers before making any decisions based on the content provided.
Last modified on November 18th, 2025 at 5:07 pm
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Frequently Asked Questions
The CoS is a required document for all Tier 2 and Tier 5 Visa applicants.
It is not required by those on the Tier 5 Youth Mobility route as the applicant’s country of origin acts as their sponsor.
Employers also do not need to sponsor Tier 1 Visa applicants.
At the Immigration Advice Service, our team of expert lawyers are immensely experienced in assisting with Certificate of Sponsorship applications. We understand that having access to as wide a talent pool as possible is an integral part of thriving as an organisation. As a result, we will guide you through the application process step-by-step, ensuring that you receive your desired outcome.
As part of our services, you will receive:
- Ensure that you are fulfilling your sponsorship duties correctly;
- Assess the role and individual you intend to hire in order to establish what CoS must be applied for;
- Assess the details of your employee’s application to ensure that all requirements are met;
- Ensure that the role being filled is either on the Shortage Occupation List (SOL) or has passed the Labour Market Test;
- Assist you in the use of the Online Management System.
A Defined CoS should be used where the applicant is applying for a Skilled Worker Visa and applying from overseas.
An Undefined CoS applies when the applicant is applying for a Skilled Worker visa from within the UK, or are applying for any other type of visa which requires a UK CoS.
