CoS Expiry & Validity

In This Article

• How long is a CoS valid?
• What happens if the CoS expires?
• Does CoS expiry affect the visa duration?
• CoS start dates and job start flexibility
• Common causes of CoS expiry issues
• What employers should do to avoid problems
• Common mistakes to avoid
• Frequently asked questions
• Related terms

How Long is a CoS Valid?

A Certificate of Sponsorship is valid for 3 months from the date it is assigned by the employer. This is not 3 months from the visa application — it is 3 months from the moment the employer clicks "assign" in the Sponsorship Management System.

The worker must submit their visa application before this 3-month window closes. The CoS reference number will be rejected in the visa application if the CoS has expired.

This validity period applies to both Defined CoS and Undefined CoS.

What Happens if the CoS Expires?

If the worker fails to submit their visa application within the 3-month validity window:

1. The CoS is marked as expired in the SMS
2. It cannot be reactivated or extended
3. The employer must issue a new CoS — consuming allocation again
4. For Defined CoS, a new Home Office approval may be needed (adding further delay)
5. The worker must start their application afresh using the new CoS reference

This is a common and frustrating situation — particularly for international candidates dealing with travel logistics, document gathering, or personal circumstances that cause delays.

Does CoS Expiry Affect the Visa Duration?

The CoS's 3-month validity is separate from the visa duration once granted. Once a visa application is made using the CoS, the CoS has served its purpose. The visa duration is determined by:

• The start and end dates recorded on the CoS for the job
• The maximum leave grant for the route (up to 5 years for Skilled Worker)

If a CoS expires and a new one is issued, the new CoS dates govern the visa. If the employer changes the start date on the new CoS, the worker's visa will reflect those updated dates.

CoS Start Dates and Job Start Flexibility

The CoS records a job start date. Workers can apply for a visa at any point within the 3-month validity window — they don't have to apply the moment it's assigned. However:

• The visa, if granted, will typically be issued with leave starting around the date of grant (not necessarily the CoS start date for entry clearance)
• Workers granted entry clearance can arrive in the UK up to 14 days before the CoS start date
• Workers should not start working before the CoS start date

If the job start date on the CoS needs to change (e.g., the role is delayed), the employer must withdraw the original CoS and issue a new one with the correct start date.

Common Causes of CoS Expiry Issues

• Worker documents take longer than expected to gather — police certificates, translated documents, reference letters
• Biometric appointment backlogs — in some countries, UKVCAS appointment slots are scarce
• Worker decides not to proceed and the employer discovers late
• Employer assigns CoS too early — before the worker is ready to apply
• Worker has a personal emergency delaying the application
• Bank statement requirements — workers sometimes fail the financial maintenance test on first attempt, requiring more savings before reapplying

What Employers Should Do to Avoid Problems

1. Coordinate timing with the worker. Before assigning a CoS, confirm the worker has all documents ready and knows the 3-month window.
2. Assign CoS as late as reasonably possible. If the start date is 4 months away, there's no need to assign the CoS immediately — wait until 8–10 weeks before the target application date.
3. Set a reminder for the worker 4 weeks before expiry. If the worker hasn't applied by then, there's time to nudge or issue a new CoS.
4. Keep allocation headroom. Ensure you have enough Undefined CoS allocation to re-issue if needed; don't allocate your last CoS to a candidate who hasn't committed.

Common Mistakes to Avoid

• Assigning a CoS the moment the contract is signed. If the start date is months away, this wastes the validity window unnecessarily.
• Not confirming with the worker that they've submitted. Employers often only find out a CoS expired when chasing for a progress update weeks later.
• Failing to budget for a replacement CoS. Re-issuing means paying the Immigration Skills Charge again if the original was already paid for an expired CoS — though ISC refund rules apply in some circumstances.
• Starting the new CoS with identical dates to the expired one. Review all details on the new CoS — dates, salary, SOC code — to ensure they're still current and correct.

Frequently Asked Questions

Can a CoS be extended beyond 3 months?

No. There is no mechanism to extend a CoS's validity. The only option is to withdraw the expired CoS and issue a new one.

Is the Immigration Skills Charge refunded if a CoS expires unused?

UKVI will refund the ISC if the CoS is withdrawn before the worker uses it for a visa application. If the CoS expired without being used (no withdrawal), you may still be able to claim a refund — contact UKVI to request this.

What if the visa is still being processed when the CoS start date arrives?

This is common. The CoS start date is an intended start date — it does not mean the worker must start on exactly that date or lose the application. The Home Office processes applications against the CoS as long as the CoS was valid when the application was submitted.

Can a worker reuse a CoS if their application was refused?

No. A CoS can only be used to submit one visa application. If refused, the worker needs a new CoS to reapply. The original CoS is "consumed" upon submission regardless of the outcome.

Related Terms

• Certificate of Sponsorship
• Defined CoS vs Undefined CoS
• Immigration Skills Charge
• Changing Visa Sponsors

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