What is a certificate of sponsorship? A job seeker's guide (UK, 2026)

A certificate of sponsorship (CoS) is an electronic record, with its own reference number, that a Home Office licensed employer assigns to you so you can apply for a UK work visa such as the Skilled Worker visa. It is not a paper certificate, you cannot apply for one yourself, and you should never pay anyone for one. This guide explains the CoS from the candidate's side: what is on it, how long it lasts, who pays for it, and how to find employers that can actually issue one. Rules were checked on gov.uk on 7 October 2026.

What is a certificate of sponsorship, exactly?

The Home Office's own sponsor guidance puts it plainly: a CoS "is not a paper certificate or document, but a database record" confirming who the employer intends to sponsor and the job they will do (Sponsor guidance part 2, August 2026). The employer creates it in the Home Office's sponsorship management system and assigns it to you.

What you receive is a CoS reference number. The Skilled Worker visa page on gov.uk says you need that number for your visa application, and you can ask your employer for a copy of the certificate itself if you want to check the details.

Two points that trip candidates up:

A CoS is not a visa. It is the employer's confirmation that they want to sponsor you. The sponsor guidance states that assigning a CoS "does not guarantee" a visa: you still have to meet every requirement of the route, including salary and English.
You cannot request one from the Home Office. Only a licensed sponsor's authorised users can assign a CoS.

Who can assign a CoS?

Only an organisation holding a sponsor licence for the right route. Every one of them is listed on the public register of licensed sponsors, which the Home Office updates most working days.

We keep a synced copy of that register. As of 7 October 2026 it holds:

Measure (our copy of the register, 7 October 2026)	Count
Organisations on the workers register, all routes	126,670
Organisations licensed for the Skilled Worker route	121,382
Skilled Worker sponsors based in London	35,255
Skilled Worker sponsors with a B rating	87

The rating matters. An A-rated sponsor can assign new certificates. A B-rated sponsor is on an action plan and, as our guide to UK companies that sponsor Skilled Worker visas explains, cannot assign new ones until it returns to an A rating. You can look up any employer's name, route and rating with our free sponsor licence check.

Defined and undefined CoS: which one will you get?

Gov.uk still uses both terms as of October 2026 (certificates of sponsorship, gov.uk):

	Defined CoS	Undefined CoS
Who it is for	Skilled Worker applicants applying from outside the UK	Skilled Workers applying from inside the UK, and all other work routes
How the employer gets it	Applies for each one individually	Assigns it from its annual allocation
Timing on gov.uk	Usually approved within one working day	Extra allocation usually decided within 12 weeks

For most international graduates already in the UK, the switch to Skilled Worker uses an undefined CoS. The practical difference for you is timing. An employer with spare undefined certificates can assign one quickly. An employer that has run out has to request more, and gov.uk says the decision usually comes within 12 weeks unless they pay for a faster one.

The sponsor guidance warns that the Home Office will normally revoke a licence if an employer assigns an undefined CoS where a defined one is required. That is one reason employers are careful about the type.

What is on a certificate of sponsorship?

Gov.uk's list of documents for a Skilled Worker application shows what the CoS covers. It includes:

your personal details (name, nationality, date of birth)
your job title and the occupation code (SOC code) for the role
your salary
the employer's name and sponsor licence number
the job's start and end dates
whether the employer will cover your maintenance for the first month (if so, you may not need to show savings)

Check every line. The guidance tells sponsors that a mistyped name can be fixed with a sponsor note, but a wrong occupation code or route, or errors in more than one of nationality, date of birth and surname, means the CoS has to be withdrawn and a new one assigned. A wrong occupation code can also change the salary you need to meet. Our Skilled Worker salary calculator shows the threshold for a given code.

How long is a CoS valid for?

You must use it in a visa application within 3 months of the date it is assigned to you (gov.uk). There is a second limit: you cannot apply more than 3 months before the job's start date shown on the certificate.

If the 3 months pass without an application, the CoS expires and the employer has to assign a new one. If you are switching from a Graduate visa, that timing has to fit inside your current permission. Our Graduate visa to Skilled Worker timeline counts back from your expiry date.

How much does a certificate of sponsorship cost, and who pays?

The employer pays. These are the figures on gov.uk as of 7 October 2026:

Cost	Amount	Paid by
CoS fee, Worker licence (includes Skilled Worker)	£525 per certificate	Employer
CoS fee, Temporary Worker licence	£55 per certificate	Employer
Immigration Skills Charge, medium or large sponsor	£1,320 for the first 12 months, then £660 per extra 6 months	Employer
Immigration Skills Charge, small or charitable sponsor	£480 for the first 12 months, then £240 per extra 6 months	Employer

Sources: certificate costs and Immigration Skills Charge on gov.uk. The sponsor guidance confirms the higher charge applies to certificates assigned on or after 16 December 2025; before that it was £1,000 and £364 for the first year.

For a five-year certificate at a large employer, the skills charge alone is £6,600. That cost is a big part of why some employers say "no sponsorship". There is one exemption that helps graduates: gov.uk says the charge is not due when someone switches to Skilled Worker from a visa that allows them to study, and the sponsor guidance lists further exemptions.

Your own costs are separate: the visa application fee and the Immigration Health Surcharge. Gov.uk shows these when you apply.

Can an employer make you repay the CoS fee or skills charge?

No, for these two costs. The Home Office sponsor guidance says:

CoS fee: sponsors "must not recoup, or attempt to recoup, by any means" any part of the CoS fee or associated admin costs from a Skilled Worker assigned a CoS on or after 31 December 2024.
Immigration Skills Charge: sponsors "must not pass on any of the ISC" to sponsored workers, and the Home Office will normally revoke the licence if they do.

Gov.uk's employer pages add that a licence may be revoked if the employer asks the worker to pay "the fee or any costs linked to your application". If a contract has a clause that claws back either cost when you leave, ask the employer about it in writing and get free advice before you sign. Citizens Advice and advisers regulated by the Immigration Advice Authority can look at your situation.

Red flags: you cannot buy a certificate of sponsorship

Because a CoS can only be assigned by a licensed sponsor through a Home Office system, there is no legitimate market for them. Treat any of these as warning signs:

someone offers a CoS "for sale", or a job "with CoS included" for a fee
an agent asks for a deposit, "sponsorship fee", "CoS processing fee" or "Immigration Skills Charge" from you
the employer is not on the register, or the name on the CoS does not match a licensed sponsor
you are offered a CoS without any interview or contract for a real job

Check the employer on the register first. If you think you have been targeted by a scam, report it to Action Fraud.

How to find jobs where an employer can issue a CoS

Search terms like "certificate of sponsorship jobs" mostly turn up job boards. A more reliable method:

Start from the register, not adverts. Browse visa sponsors by city and shortlist licensed employers in your field.
Check the rating and route. You want an A rating on the Skilled Worker route.
Check the role meets the rules. The job needs an eligible occupation code and must meet the salary threshold. Our guide to the graduate salary threshold covers new-entrant rates.
For graduate schemes, read the employer's own policy. Our graduate visa sponsorship pages record what each employer publishes, with sources and the date we checked.
Watch for changes. Licences are suspended and revoked every week. Our monthly register changes show who was added and removed.

Frequently asked questions

Is a certificate of sponsorship the same as a visa? No. A CoS is the employer's electronic confirmation that it wants to sponsor you for a specific job. You still have to apply for the visa and meet all its requirements, and gov.uk's sponsor guidance says a CoS does not guarantee a grant.

How long is a certificate of sponsorship valid? You must use it in a visa application within 3 months of the date it was assigned to you. You also cannot apply more than 3 months before the job's start date on the certificate.

How much does a certificate of sponsorship cost? As of October 2026 gov.uk lists £525 per certificate for Skilled Worker and other Worker routes, and £55 for Temporary Worker routes. The employer pays this, plus any Immigration Skills Charge of £1,320 a year (large sponsors) or £480 a year (small or charitable sponsors).

Can I apply for a certificate of sponsorship myself? No. Only a licensed sponsor can assign one, through the Home Office sponsorship management system. Your route to a CoS is a job offer from an employer on the register of licensed sponsors.

Can my employer ask me to pay back the Immigration Skills Charge? No. The Home Office sponsor guidance says sponsors must not pass on or recoup the skills charge, and the same applies to the CoS fee for Skilled Worker certificates assigned on or after 31 December 2024. A sponsor that does this risks losing its licence.

What is the difference between a defined and an undefined CoS? A defined CoS is for Skilled Worker applicants applying from outside the UK and is requested case by case. An undefined CoS is for Skilled Workers applying from inside the UK and for other routes, and comes from the employer's yearly allocation.