Certificate of Sponsorship UK What It Is and How It Works

The Immigration Skills Charge increased by 32% in December 2025 under HC 1333. The charge is payable by the employer and cannot legally be passed to the sponsored worker recovering it by deduction from salary, by a clause in the employment contract, or by any other means is a prohibited act under the sponsor guidance and a primary trigger for compliance investigation and licence revocation.

How to Get a Certificate of Sponsorship UK The Assignment Process

Assigning an Undefined CoS (for workers inside the UK)

Step 1: Log into the Sponsor Management System at gov.uk/sponsor-management-system. Navigate to the CoS management section.

Step 2: Select "Assign a CoS" and choose Undefined CoS. Check that you have sufficient Undefined CoS allocation — the allocation available is shown in the SMS dashboard.

Step 3: Enter the worker's details: full name (matching passport exactly), date of birth, SOC code, gross annual salary, job title, start date, and contracted hours. Double-check every field before confirming.

Step 4: Pay the CoS assignment fee (£239) and the Immigration Skills Charge through the SMS payment portal.

Step 5: The CoS reference number is generated immediately on successful payment. Provide the 14-character reference number to the worker so they can enter it in their visa application.

Requesting Defined CoS (for workers outside the UK)

If the worker is applying from outside the UK, the employer must have Defined CoS allocation. The Home Office allocates Defined CoS annually based on sponsor need declarations. If allocation is insufficient, the employer must request more through the SMS and wait for the Home Office to allocate additional certificates this process typically takes 2 to 4 weeks.

The assignment process for Defined CoS is the same as for Undefined CoS once allocation is confirmed.

Certificate of Sponsorship Processing Time

An Undefined CoS is generated immediately in the SMS once the assignment form is completed and payment is made there is no processing time. The reference number is available within minutes.

A Defined CoS request where additional allocation is needed from the Home Office typically takes 2 to 4 weeks to be processed by the Home Office. In practice, employers with established sponsor licences and a history of Defined CoS usage are often allocated their annual request in advance. Planning CoS needs for overseas recruitment several weeks ahead avoids delays.

Certificate of Sponsorship Priority Service

There is no separate priority service for CoS assignment itself. An Undefined CoS is generated immediately and there is nothing to expedite. A Defined CoS request where additional allocation is needed does not have a priority route the 2 to 4 week timeline applies regardless.

However, once the CoS has been assigned, the worker can choose to pay for Priority or Super Priority processing of their visa application (£500 or £800 additional respectively). This expedites the visa decision, not the CoS assignment.

Documents Required for Certificate of Sponsorship UK

There are no supporting documents submitted with the CoS assignment itself the assignment is made entirely through the SMS by entering data. However, the employer must have the following information available and verified before completing the assignment:

From the worker's passport: Full legal name exactly as it appears (including middle names if shown), date of birth, passport number, and nationality.

Employment details: SOC 2020 occupation code, confirmed gross annual salary meeting both the general threshold and the going rate, proposed start date, contracted hours, and job title.

Salary evidence: Internal payroll confirmation that the stated salary will be paid in every pay period, and that it meets the going rate for the SOC code as published in Appendix Skilled Occupations.

Genuine vacancy evidence: Internal documentation confirming the role has been properly approved, the job description accurately describes the duties, and the role is a genuine business requirement.

What Happens if the CoS Contains Errors

Errors on a CoS cannot be corrected after the worker has used it to submit a visa application. This is the most important operational risk of the CoS process.

Error identified before the application is submitted: The employer can withdraw the CoS through the SMS and assign a corrected one. A new assignment fee and ISC is payable for the replacement CoS.

Error identified after the application is submitted: The worker must withdraw the application. The employer assigns a new CoS with the correct details. The worker reapplies. The original visa application fee is non-refundable the worker pays again.

Error identified during Home Office processing: If the mismatch between the CoS and the passport (name, date of birth) is identified by the Home Office, the application is rejected as invalid. If a salary or occupation code discrepancy is identified, the application may be refused on eligibility grounds. In serious cases particularly where the discrepancy suggests an attempt to circumvent the salary threshold the employer may face a compliance investigation.

CoS Validity The Three-Month Window

A Certificate of Sponsorship is valid for three months from the date it is assigned in the SMS. The worker must submit their visa application within that three-month period. If the application is not submitted before the CoS expires, the CoS becomes invalid. The employer must assign a new CoS paying a new assignment fee and ISC and the worker must apply with the new reference number.

For overseas workers who need to attend a Visa Application Centre and book biometric appointments, three months can be tight. The employer and worker should coordinate CoS assignment timing so the worker has sufficient time to complete all application steps within the validity window. For workers in countries with limited VAC appointment availability, this coordination is critical.

Frequently Asked Questions

What is a Certificate of Sponsorship?

A Certificate of Sponsorship is a unique reference number generated by a licensed UK employer through the Home Office's Sponsor Management System. It records the key details of a job offer the occupation code, salary, start date, and employer information and enables the worker to apply for a Skilled Worker or other sponsored work visa. Without a CoS, the worker cannot apply.

What is the difference between a Defined and Undefined Certificate of Sponsorship?

A Defined CoS is used for workers applying from outside the UK (entry clearance). Employers must request Defined allocation from the Home Office in advance. An Undefined CoS is used for workers already in the UK who are switching to or extending a Skilled Worker visa. Employers can assign Undefined CoS directly through the SMS without pre-approval, subject to having sufficient allocation.

How much does a Certificate of Sponsorship cost in 2026?

The CoS assignment fee is £239. The Immigration Skills Charge is additional: £1,320 per year for large employers (from December 2025) or £480 per year for small employers and charities. For a large employer sponsoring a worker on a 5-year visa, the total employer cost is £239 + £6,600 = £6,839. These costs cannot be passed to the worker.

How long does it take to get a Certificate of Sponsorship?

An Undefined CoS (for a worker inside the UK) is generated immediately in the SMS on payment there is no processing time. A Defined CoS where the employer has sufficient existing allocation is also immediate. Where additional Defined CoS allocation must be requested from the Home Office, the process takes 2 to 4 weeks.

Can I correct a Certificate of Sponsorship after it has been used?

No. Once a worker has used a CoS reference number to submit a visa application, the CoS cannot be corrected. The worker must withdraw the application, the employer must assign a new CoS with the correct details, and the worker must reapply paying a new visa application fee. Always verify every field against the passport before the CoS is assigned.

What is the CoS validity period?

Three months from the date of assignment. The worker must submit the visa application within this window. If the CoS expires before the application is submitted, a new CoS must be assigned and a new fee paid.

What documents are required for a Certificate of Sponsorship?

No documents are submitted with the CoS the assignment is completed through the SMS by data entry. The employer must have the worker's passport details (full legal name, date of birth), the correct SOC 2020 code, a confirmed salary meeting both the general threshold and the going rate, a proposed start date, and contracted hours verified before beginning the assignment.