UK Certificate of Sponsorship (CoS)

Understanding the Certificate of Sponsorship (CoS):

The CoS is mandatory for visa applications under the sponsored routes, including skilled workers, temporary workers and the global business mobility routes. The CoS is a virtual document, generated through an online portal, which can be accessed following a successful sponsor licence application. Each COS contains a unique reference number which is assigned by the sponsor to the worker for their visa application. The CoS confirms the job occupation code, salary, start and end date of employment, as well as details of the sponsor and the worker.

Unsponsored routes, such as Graduate and Global Talent, do not require a CoS. These routes do not require a “job offer” or a sponsor.

A CoS is needed for most work visas and shows that the employee has a job offer and that they meet the necessary requirements.

Types of CoS

There are two types of CoS: defined and undefined.

Defined CoS: These are for Skilled Workers who are applying for entry clearance to enter and work in the UK.

Undefined CoS: these are for:

– Skilled Workers who are applying for permission to stay from within the UK;
– those you may be switching from different categories within the UK 

A sponsor must understand the difference between the two types of CoS and assign the correct type to their workers. Their sponsor licence may be revoked if it is not done properly.

Becoming a sponsor, authorised by the Home Office to sponsor workers is a privilege that comes with duties and obligations that must be carried out to ensure compliance. Our immigration team at Davenport Solicitors is committed to assisting organisations with sponsor licence applications, assigning CoS and operating the Sponsorship Management System (SMS). We strive to ensure your organisation’s continuous compliance with the ever-changing immigration rules.

Process of Obtaining a Certificate of Sponsorship

  1. Sponsor Licence: The employer must have a valid sponsor licence from the Home Office.
  2. Job Offer: The employer offers a job to a worker..
  3. Assigning the CoS: The employer assign the appropriate CoS to the worker through the Home Office online system, known as the sponsor management system (SMS).
  4. CoS Number: The worker receives a CoS number, which they use to apply for their visa.
  5. Visa Application: The worker uses the CoS  to complete their visa application.

Some of the types of Visas that Require a Certificate of Sponsorship

  1. Skilled Worker visa
  2. Health & Care Worker visa
  3. Temporary Worker visas, including, seasonal worker, government authorised exchange, international agreement, religious worker and charity worker routes
  4. Global Business Mobility visas including: senior or specialist worker, graduate trainee, UK expansion worker, service supplier and secondment worker routes
  5. Scale Up worker

Sponsor licence vs CoS

A sponsor licence and a CoS are not the same thing. In the realm of business, a sponsor licence is permission granted by the UKVI by which an organisation can employ or sponsor workers to come and work in the UK. Only organisations with a valid sponsor licence (“sponsors”) can assign a CoS to their prospective workers.

Based on their business need, a sponsor can request for CoS allocation (the number of CoS required). Once granted, the sponsor can assign it to each prospective worker for their visa applications, including extensions. A CoS is valid for 3 months from the date it is assigned. A visa application should be made using the CoS within this 3-month period.

If the worker’s job changes during their employment, a new CoS may be required.

FAQs about the Certificate of Sponsorship

What is a Certificate of Sponsorship?

It is a virtual document, given by an employer to a worker, which is then used by the employee to make a visa application. 

Who needs a Certificate of Sponsorship?

Workers who are being sponsored to work in the UK 

Can an employee change employer while on a CoS?

Yes, but they will need a new CoS from their new employer and may need to apply for a new visa.

Can a CoS be used more than once?

No, a CoS is unique to each job and worker. 

How long is a CoS valid for?

A CoS is valid for three months from the date it is issued.

What information is included in a CoS?

It includes details about the job, salary, worker’s personal details and confirmation that the worker meets visa requirements.

Can the Home Office revoke a CoS?

Yes, if the sponsor fails to comply with their duties, the CoS can be revoked along with the sponsor licence.

Contact us

At Davenport Solicitors, we recognise the importance of the CoS in the immigration process and are committed to assisting our clients in obtaining and using it effectively. If you require expert guidance on Certificate of Sponsorship matters or any other immigration-related concerns, please do not hesitate to contact us. Our dedicated team is here to help you navigate the complexities of UK immigration law with precision and care, ensuring a smooth and successful journey for all parties involved. Contact us


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