Certificate of Sponsorship explained

If you are applying for a UK Skilled Worker visa, the Certificate of Sponsorship, usually shortened to CoS, is the single document the whole application hangs on. It causes more confusion than any other part of the process, mostly because people expect a paper certificate. It is not one.

What a CoS actually is

A CoS is an electronic record created by your employer in the Home Office sponsorship system. You never receive a physical document. What you receive is a reference number, and you enter that number into your visa application.

The record contains your personal details, the job title and occupation code, the salary, the start and end dates, and the work location. Everything the Home Office needs to check the role against the rules.

Who can issue one

Only an organisation holding a valid sponsor licence. If the company is not on the register of licensed sponsors, no CoS exists and no Skilled Worker application is possible. This is why the sponsor register is the right starting point for a UK job search, as we cover in our guide on finding UK companies that sponsor visas.

The sequence, step by step

1. You interview and receive a job offer from a licensed sponsor.
2. The employer confirms the role is eligible, sits on an eligible occupation code and pays at or above the relevant salary threshold and going rate.
3. The employer assigns the CoS in their sponsorship management system and sends you the reference number.
4. You apply online for the Skilled Worker visa using that number, pay the fee and the immigration health surcharge, and provide biometrics.
5. You receive a decision, typically in weeks rather than months for applications made outside the UK.

Timings that matter

Assignment. Once the employer decides to assign a CoS it is usually quick, often the same week. Delays are almost always internal approval, not the Home Office.

Validity. A CoS is valid for three months from assignment. You must submit your visa application within that window or the employer has to issue a new one.

Start date. The date on the CoS can be moved later without a new certificate in many cases, but confirm with the employer before assuming.

What commonly goes wrong

Wrong occupation code. If the employer picks a code that does not match the actual duties, the application can be refused. This is the most common avoidable error and it is worth politely checking the code they intend to use.

Salary below the going rate. The salary on the CoS must clear both the general threshold and the going rate for that specific code. An employer who has not sponsored before sometimes misses the second one.

Details that do not match your passport. Names, dates of birth and passport numbers must match exactly. A single typo means a new CoS.

A licence that lapses. Rare, but if the employer loses or fails to renew its licence, the CoS becomes worthless.

What you should do as the candidate

Ask three questions before you resign from anything.

Which occupation code will the role be sponsored under? What salary will appear on the CoS? When do you plan to assign it?

An employer who has sponsored before will answer these in one email. One who cannot answer needs more time than they think, and you should plan accordingly.

Costs

The employer pays the sponsor licence fee, the CoS assignment fee and, in most cases, the Immigration Skills Charge. Those cannot legally be passed to you. You pay the visa application fee and the immigration health surcharge, which is the larger of the two for most families. Budget for it early.

Where to go next

For the thresholds, the salary rules and the full application path, read our UK Skilled Worker visa guide. If you want help getting to the offer that produces a CoS in the first place, book a free 30 minute consultation.