A sponsor licence holder can apply for a number of Certificates of Sponsorship (CoS), which they can then use for the applicants whom they intend to sponsor. A COS is not an actual certificate or paper document but is a virtual document, similar to a database record.

Sponsor must give this reference number to a migrant whom they wish to employ because it will be a key part of their application for permission to come to the UK if they are overseas (known as ‘entry clearance’), or permission to stay in the UK if they are already here (known as ‘leave to remain’).

A CoS can be following types under the Skilled Worker route – ‘Defined CoS’ and ‘Undefined CoS’.

Undefined Certificate of sponsorship (CoS)

The Undefined CoS can only be assigned to a Skilled Worker who will be applying for permission to stay from within the UK (in-country applications). A sponsor can have annual allocations of undefined certificates of sponsorship.

Defined Certificate of sponsorship (CoS)

A defined Certificate of sponsorship can only be assigned to a Skilled Worker who will be applying for entry clearance from outside the UK.

A sponsor cannot apply for an annual allocation of defined CoS. They can only apply for a defined CoS as and when they require one.

Any certificate of sponsorship is valid for a period of three (3) months from the date of issue. Once a Certificate of Sponsorship is issued, a sponsor is held fully responsible for the actions of the employee. Non-compliance of the rules may result in either the withdrawal of the Certificate or demoting the sponsor to a lesser rank.