Guide · 4 min read
How the UK Certificate of Sponsorship Works in 2026: Costs, Types, and Common Mistakes
The Certificate of Sponsorship is a critical part of every UK work visa application. Here is everything you need to know about how it works and mistakes to avoid.
What Is a Certificate of Sponsorship?
A Certificate of Sponsorship (CoS) is not actually a certificate or a physical document. It is a digital reference number generated by your employer through the Home Office's Sponsorship Management System (SMS). Think of it as a unique code that links your visa application to a specific job with a specific employer.
Without a valid CoS, you cannot apply for a Skilled Worker visa, Health and Care visa, or most other sponsored work visas.
How Much Does It Cost?
The CoS assignment fee jumped significantly in 2025:
| Item | Cost | |---|---| | CoS assignment fee | £525 per certificate | | Previous fee | £239 | | Increase | More than double |
This fee is paid by the employer, not the visa applicant. However, many employers factor this cost into their hiring decisions, so it can indirectly affect your chances of getting sponsored.
Two Types of CoS
There are two types, and it matters which one your employer uses:
Defined CoS: Used when you are applying from outside the UK. Your employer needs to request this specifically from the Home Office, and there is a limited allocation.
Undefined CoS: Used when you are already in the UK and switching visa categories or extending your stay. These are assigned from the employer's existing allocation.
The 3-Month Rule
Once your employer assigns a CoS, you have 3 months to submit your visa application. If you miss this window, the CoS expires and your employer has to assign a new one (and pay again).
This is one of the most common mistakes. Do not let your employer assign the CoS until you are ready to apply.
What Information Goes on a CoS?
The CoS contains key details about your job that the Home Office uses to assess your visa application:
- Your job title and SOC code
- The salary being offered
- Working hours
- The job location
- Start date
- Whether the role qualifies for any salary discounts
The April 2026 Salary Change
From 8 April 2026, the Home Office will check salary compliance per pay period, not just based on the annual figure. This is a big deal.
Previously, if your CoS said £41,700 annual salary, the Home Office mainly checked that headline number. Now they will look at actual payslips to make sure you are being paid the correct amount in every pay period.
This means employers cannot offer a lower monthly salary and make up the difference with year-end bonuses.
Common CoS Mistakes That Get Visas Refused
Wrong SOC code. If the job duties do not match the Standard Occupational Classification code on the CoS, the visa will be refused. Employers need to pick the code that genuinely reflects what the worker will be doing.
Salary below the threshold. The salary on the CoS must be at least £41,700 or the going rate for the SOC code, whichever is higher. Getting this wrong is an automatic refusal.
Expired CoS. As mentioned, you have 3 months. Missing this deadline is surprisingly common.
Job does not meet RQF Level 6. Since July 2025, the role must be degree-level. If the job is classified below this, it will not qualify.
Incorrect working hours. The salary must be pro-rated correctly if the job is part time. A 20-hour-per-week role at £41,700 FTE is fine, but the actual pay will be lower and the CoS needs to reflect this accurately.
How Long Does It Take?
For Defined CoS (applying from outside the UK), the employer submits a request and the Home Office typically processes it within a few working days. During busy periods this can take longer.
For Undefined CoS, the employer can assign it immediately from their allocation.
Can a CoS Be Transferred?
No. A CoS is tied to a specific employer and a specific role. If you change jobs, your new employer must assign a brand new CoS. You will also need to submit a new visa application.
Tips for Applicants
- Make sure your employer has an active sponsor licence before accepting a job offer. You can check this on the Home Office register or use the WiseRoute directory.
- Do not rush the CoS assignment. Wait until all your documents are ready so you can apply quickly once it is issued.
- Double check that the job title, salary, and SOC code on the CoS match what was discussed. Errors at this stage cause refusals.
- Keep a copy of the CoS reference number safe. You will need it for your visa application form.