BY: Naeem Uddin
Hiring overseas workers in the UK requires employers to follow strict immigration rules set by the UK Home Office. One of the most important parts of this process is the Certificate of Sponsorship (CoS). Whether you are a UK employer planning to sponsor foreign workers or an applicant applying for a Skilled Worker visa, understanding how a Certificate of Sponsorship works is essential.
In this guide, we explain what a Certificate of Sponsorship is, how it works, who needs it, the different types of CoS, costs involved, and the responsibilities of UK sponsors in 2026.
A Certificate of Sponsorship (CoS) is an electronic document issued by a UK employer that holds a valid sponsor licence from the UK Home Office. It is not a physical certificate but a digital reference number used by migrant workers when applying for a UK work visa.
The Certificate of Sponsorship confirms that:
Without a valid CoS, most overseas workers cannot apply for UK work visas such as the Skilled Worker visa or Global Business Mobility routes.
If your business wants to sponsor overseas workers legally, obtaining a sponsor licence is the first step. How to Get a Sponsorship Licence in the UK
Most foreign nationals applying for UK work visas require a Certificate of Sponsorship from a licensed UK sponsor.
A CoS is commonly required for:
The employer must first obtain a sponsorship licence before assigning a CoS to the worker.
Certain visa categories do not require sponsorship, including:
These routes allow individuals to work in the UK without employer sponsorship.
There are two main types of Certificates of Sponsorship in the UK:
A Defined CoS is used for workers applying for a Skilled Worker visa from outside the UK.
Before assigning the certificate, the employer must request approval from the Home Office through the Sponsorship Management System (SMS).
An Undefined CoS is used for:
Employers usually receive an annual allocation of Undefined CoS based on business requirements.
Choosing the correct type of CoS is important because incorrect usage can result in visa refusals or compliance issues.
To issue a Certificate of Sponsorship, a UK employer must first hold a valid sponsor licence.
The process usually involves:
The employer submits an online sponsor licence application to the UK Home Office along with supporting documents.
Once approved, the employer gains access to the Sponsorship Management System (SMS).
The employer creates and assigns a CoS to the worker through the SMS portal.
The worker uses the CoS reference number to submit their UK visa application.
The Certificate of Sponsorship usually contains:
A CoS must be used within 3 months of being assigned.
Businesses that need professional support with sponsor licence applications and compliance can learn more here: UK Sponsor Licence Services
The UK government charges employers for assigning Certificates of Sponsorship.
Current CoS fees include:
|
CoS Type |
Fee |
|
Worker CoS (Skilled Worker & Senior Worker) |
£525 |
|
Temporary Worker CoS |
£55 |
|
International Sportsperson (Over 12 Months) |
£525 |
|
International Sportsperson (Up to 12 Months) |
£55 |
In addition to CoS fees, employers may also need to pay:
UK employers are generally prohibited from passing sponsorship costs such as sponsor licence fees or Immigration Skills Charges onto workers.
Holding a sponsor licence comes with ongoing compliance duties. UK employers must maintain proper HR systems and accurate worker records at all times.
Sponsor responsibilities include:
Failure to meet sponsor duties can result in:
The UK Home Office can conduct compliance audits and site visits at any time.
Businesses sponsoring overseas workers should regularly review their compliance procedures to avoid immigration breaches. Employers needing assistance with compliance management can explore professional sponsor licence support services here: Sponsor Licence Compliance Support
Answer: No. A sponsor licence allows an employer to sponsor workers, while a Certificate of Sponsorship is assigned to an individual worker for their visa application.
Answer: The cost depends on the visa type. A Skilled Worker CoS currently costs £525, while Temporary Worker CoS costs £55.
Answer: A CoS must usually be used within 3 months from the date it is assigned by the employer.
Answer: No. Most UK work visa routes require a valid Certificate of Sponsorship before a visa application can be submitted.
Answer: Yes. If employment circumstances change or sponsorship conditions are breached, the employer can withdraw or cancel the CoS through the Sponsorship Management System.
Applying for a sponsor licence and managing Certificates of Sponsorship can be complicated for UK businesses. From compliance checks to assigning CoS correctly, employers must meet strict Home Office requirements.
Professional immigration support can help businesses:
If your organisation needs assistance with UK sponsor licensing or sponsoring overseas workers, expert guidance can make the process smoother and fully compliant.
