Issuing a certificate of sponsorship

You can issue a Certificate of Sponsorship (CoS) through the online Sponsor Management System. A CoS can only be assigned by a Level 1 or Level 2 user.


A CoS is a virtual document and not a physical certificate. To assign the CoS your Level 1 or 2 user must create a unique reference number. You should give this to the overseas (migrant) worker because they will need to use it in their application for a visa.

They may also need other information from you for their application. The CoS does not guarantee a visa or the right to work in the UK and each CoS can only be used once.

Certificates of Sponsorship

There are two types of CoS under the Skilled Worker Route:

  • A Defined COS – this is for Skilled Workers who are outside of the UK and will be applying for their visa from overseas
  • An Undefined COS – this is for Skilled Workers who are already inside the UK and will be applying for their visa to work for you from inside the UK.

A Defined COS will be applied for as and when required (you cannot apply for an annual allocation of this type).  This is done via the SMS and certain mandatory information needs to be provided. Decisions on this type of COS (where the application is straight forward) will normally take around 1 working day.

You can apply for an annual allocation for Undefined COS and these should be used where the skilled worker is already in the UK. If there are no CoS left in your allocation to sponsor the worker, it is possible to apply to increase the allocation.

It is important to understand the difference between the two types of COS, if the wrong type of CoS is assigned, or false information is provided on an application for a defined CoS, UKVI may revoke the sponsor licence in place.

When you are assigning a COS you are also confirming that the genuine vacancy test has been met. For more information on the genuine vacancy test, see the Policy Guidance for Sponsors.