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. Not 3 months from the visa application. Three months from the moment the employer clicks "assign" in the Sponsorship Management System.

The worker must make a valid visa application before this window closes, or the CoS expires.

There is a second limit: the worker can't apply for a visa more than 3 months before the start date on the CoS. So an application can only be made from 3 months before the job's start date until 3 months after the CoS was assigned.

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 assign, and pay for, a new CoS
4. For a Defined CoS, the employer has to apply for a new one, which GOV.UK says is usually approved within one working day
5. The worker must start their application afresh using the new CoS reference

This happens more often than you might think. International candidates juggling travel logistics, document gathering, or personal emergencies can easily miss the window.

Does CoS Expiry Affect the Visa Duration?

No. The CoS's 3-month validity and the visa duration are separate things. Only the application date counts for the 3 months: once the worker has used the CoS in a valid application, it does not need to stay valid until the Home Office decides. A Skilled Worker's permission usually runs until 14 days after the end date recorded on the CoS, and that end date can be up to 5 years after the start date.

If a CoS expires and a new one is issued, the new CoS dates govern the visa. Changed 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. You can apply for a visa at any point within the 3-month validity window, but not more than 3 months before that start date. There is no requirement to apply the moment it is 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
• Once a worker has permission to enter or stay in the UK, they can start work, even if that is before the start date on the CoS. They should normally start no later than 28 days after the latest of the CoS start date, the "valid from" date on their visa and the date they are notified of the grant

If the job start date changes before the worker has applied, or before the Home Office has decided their application, the employer should report it by adding a sponsor note to the CoS, because it can affect the period of permission granted. It doesn't need to withdraw the CoS for that. A significant error, such as the wrong occupation code, does mean withdrawing it and assigning a new one.

Common Causes of CoS Expiry Issues

Documents often take longer than expected to gather: police certificates, translated documents, reference letters. Biometric appointment backlogs make things worse, especially in countries where visa application centre appointments are scarce. Sometimes the worker decides not to proceed and the employer only finds out weeks later.

Other common causes include employers assigning the CoS too early (before the worker is ready to apply), personal emergencies on the worker's side, and bank statement shortfalls where the worker fails the financial maintenance test on first attempt and needs more time to save.

What Employers Should Do to Avoid Problems

1. Coordinate timing with the worker. Before assigning a CoS, confirm they have all documents ready and understand the 3-month window.
2. Assign the CoS as late as reasonably possible, but early enough that the worker can still apply. They can't apply more than 3 months before the start date, and GOV.UK tells employers to make sure the timing doesn't leave the worker unable to make a successful application.
3. Set a reminder 4 weeks before expiry. If the worker has not applied by then, there is still time to nudge or issue a new CoS.
4. Keep allocation headroom. Make sure you have enough Undefined CoS allocation to re-issue if needed. Do not allocate your last CoS to a candidate who has not committed.

Common Mistakes to Avoid

Assigning a CoS the moment the contract is signed is a frequent error. If the start date is months away, you are burning the validity window for no reason. Similarly, many employers never confirm that the worker has actually submitted their application, and only discover the CoS expired when chasing for a progress update weeks later.

On the financial side, a replacement CoS has to be paid for, so the certificate fee (£525 for a Skilled Worker) is paid again, along with any Immigration Skills Charge that applies. GOV.UK says the skills charge paid on the expired CoS is refunded in full, with a decision normally within 90 days of the expiry date. And when you do issue a replacement, review every detail on the new CoS, including dates, salary and SOC code, to make sure they are still current.

Frequently Asked Questions

Can a CoS be extended beyond 3 months?

No. A CoS that isn't used within 3 months of being assigned expires, and GOV.UK says the employer must then assign, and pay for, a new one.

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

Yes. GOV.UK says the Immigration Skills Charge is refunded in full if the CoS expires before it is used in a valid application, or if the employer withdraws it before it is used. UKVI normally decides within 90 days of the expiry or withdrawal date, and the employer should contact UKVI if the refund hasn't been paid by then. The certificate fee is not refunded when a CoS is withdrawn.

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

If the start date changes before the Home Office has decided the application, the employer should report it by adding a sponsor note to the CoS, because it can affect the period of permission granted. Once permission is granted, there is a 28-day limit. The worker should normally start no later than 28 days after the latest of three dates: the CoS start date, the 'valid from' date on their visa and the date they are told of the grant.

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

Not after a decision. Once the Home Office has granted or refused an application, the CoS shows as 'used' and can't support another one. If the application is refused, and any administrative review is dismissed, the employer must assign and pay for a new CoS. An application that is rejected as invalid or withdrawn doesn't use up the CoS, so the worker can use it again for another application as long as it hasn't expired.

Related Terms

• Certificate of Sponsorship
• Defined CoS vs Undefined CoS
• Immigration Skills Charge (GOV.UK)
• Changing Visa Sponsors

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