A certificate of sponsorship (CoS) is an electronic record that a licensed UK employer assigns to a worker from overseas it wants to employ. It is not a paper document. It carries a unique reference number, which the worker enters on their visa application to show that an approved sponsor has offered them an eligible job.
Key points
- It is a record on the Home Office sponsorship management system, not a physical certificate.
- The worker must use it to apply for their visa within 3 months of it being assigned.
- A defined certificate is for a Skilled Worker applying from outside the UK. An undefined certificate covers Skilled Workers applying from inside the UK and every other sponsored route.
- The employer pays to assign it: £525 on most Worker routes and £55 on Temporary Worker routes.
- A certificate is not a visa. The Home Office still decides the worker's application.
How a certificate of sponsorship works
An employer must hold a sponsor licence before it can sponsor anyone. Once it does, it assigns a certificate of sponsorship to each overseas worker it wants to employ.[1]Home Office, UK visa sponsorship for employers: Certificates of sponsorship The employer does this online, through the Home Office sponsorship management system.
Before assigning it, the employer checks that the worker and the job meet the rules for the route. The certificate records the result: who the worker is, what the job is and what it pays. The worker receives a reference number and enters it on their visa application.[2]Home Office, Skilled Worker visa: Your job
Two time limits apply. The worker must apply for their visa within 3 months of the certificate being assigned. They also must not apply more than 3 months before the start date of the job shown on it.[1]Home Office, UK visa sponsorship for employers: Certificates of sponsorship
Defined and undefined certificates
There are two kinds. Which one an employer needs depends on where the worker is applying from and on which route.[1]Home Office, UK visa sponsorship for employers: Certificates of sponsorship
| Defined certificate | Undefined certificate | |
|---|---|---|
| Who it is for | A Skilled Worker applying from outside the UK | A Skilled Worker applying from inside the UK, and applicants on all other sponsored routes |
| How the employer gets it | Applies for each one through the sponsorship management system | Estimates a yearly number when applying for the licence, and can request more later |
| How long a decision takes | Usually approved within one working day | A request for extra certificates usually takes up to 12 weeks, or 5 working days with the paid service |
Both timescales can be longer if UK Visas and Immigration needs to make further checks.
What a certificate of sponsorship costs
The employer pays a fee each time it assigns a certificate. The amount depends on the type of licence.[1]Home Office, UK visa sponsorship for employers: Certificates of sponsorship
| Route | Fee per certificate |
|---|---|
| Worker routes, including Skilled Worker | £525 |
| Temporary Worker routes | £55 |
| International Sportsperson, certificate for more than 12 months | £525 |
| International Sportsperson, certificate for 12 months or less | £55 |
For a Skilled Worker or a Senior or Specialist Worker, the employer may also have to pay the immigration skills charge at the same moment. That charge is £1,320 for the first 12 months and £660 for each further 6 months for a medium or large sponsor. For a small or charitable sponsor it is £480 and then £240.[3]Home Office, UK visa sponsorship for employers: Immigration skills charge
Example
A medium-sized company sponsors a software developer from outside the UK on a Skilled Worker visa for 3 years.
- Certificate of sponsorship: £525
- Immigration skills charge, first 12 months: £1,320
- Immigration skills charge, four further periods of 6 months at £660: £2,640
The employer pays £4,485 when it assigns the certificate. If the same company were a small sponsor, the skills charge would be £480 plus four payments of £240, and the total would be £1,965.
These are the employer’s costs. The worker’s own visa fee and Immigration Health Surcharge are separate. The figures were correct on the date shown at the top of this page, and fees change.
What people get wrong
Many applicants treat the certificate as the approval. It is not. It is the employer’s statement to the Home Office that the job and the worker meet the rules. The visa decision comes afterwards, and it can still be a refusal.
The second common mistake is on cost. On the Skilled Worker route the employer must pay the certificate fee and the immigration skills charge itself. GOV.UK guidance says a sponsor’s licence may be revoked if it asks the worker to pay them.[1]Home Office, UK visa sponsorship for employers: Certificates of sponsorship[3]Home Office, UK visa sponsorship for employers: Immigration skills charge
The bottom line
A certificate of sponsorship is the link between a licensed employer and a worker’s visa application. The employer assigns it and pays for it. The worker uses its reference number to apply within 3 months. It shows that a sponsor stands behind the job, and it leaves the decision on the visa with the Home Office.
Common questions
No. The certificate shows that a licensed employer is sponsoring you for a specific job. You still have to apply for the visa itself and the Home Office decides that application.
You must use it to apply for your visa within 3 months of your employer assigning it. You also cannot apply more than 3 months before the job start date shown on the certificate.
No. Only an employer that holds a sponsor licence can assign one. Your employer assigns it through the sponsorship management system and gives you the reference number.
On the Skilled Worker route and several others, the employer must pay the certificate fee itself. GOV.UK guidance says a licence may be revoked if the sponsor asks the worker to pay it.
Sources
We cite the Immigration Rules, legislation and GOV.UK guidance directly. Rules change, so each source shows the date we last checked it.
- Home Office. UK visa sponsorship for employers: Certificates of sponsorship. Checked 11 November 2026. ↩
- Home Office. Skilled Worker visa: Your job. Checked 11 November 2026. ↩
- Home Office. UK visa sponsorship for employers: Immigration skills charge. Checked 11 November 2026. ↩