⏳ CoS Expiry Dates Explained
Both Defined and Undefined Certificates of Sponsorship have expiry dates. If a CoS is not assigned before its expiry date, it cannot be used.
🔹 Defined CoS Expiry
Defined CoS expire 3 months after they are granted by the Home Office.
This means you have a 3-month window from the approval date to assign the CoS to a candidate.
🔴 Undefined CoS Expiry
Undefined CoS expire on the same date each year — your CoS expiry date.
For example, if your expiry date is 15th February every year, any unassigned CoS will expire after this date, even if approved the day before (e.g., 14th February).
🔍 How to Check Your CoS Expiry Dates
You can view your CoS expiry dates easily in Borderless:
Go to the Home page
Navigate to 'CoS Allocation' on the Home page.
This will show you how many CoS you have available and the expiry dates relevant to your allocations.
✅ Using a CoS Once It Is Assigned
The expiry dates above are about assigning a CoS in time. Once a CoS has been assigned to a worker, a separate deadline applies: the worker must submit their visa application, quoting that CoS reference, within 3 months of the date it was assigned.
A CoS counts as used once the worker has submitted and paid for a valid application using the reference. The biometric enrolment appointment is a separate follow-up step. It can take place after the CoS expiry date without affecting the CoS, as long as the application itself was submitted in time.
If the application has not been submitted before the CoS expires, that is a different situation and the CoS may no longer be usable. If you are unsure whether an application has been submitted in time, please contact us before the deadline.
⏳ How Early a CoS Can Be Used
Assigning a CoS in time is only half the picture. There is also a limit on how early the worker can apply.
A worker can apply up to 3 months before the start date shown on their CoS (sponsor guidance SK3.33). If the start date is further away than that, the application cannot be made yet, even though the CoS has been assigned and even though the SMS will let you enter the dates.
This matters most when you have CoS about to expire and a worker whose current permission still has some time to run. If a worker's permission ends in mid January, the sensible start date on a new CoS is the day after that, so the application cannot go in until around mid October. CoS expiring before then cannot be held back and used for that worker.
If your allocation expires before you can assign the CoS, you will need to request additional CoS when you do come to sponsor.
Home Office guidance: Skilled Worker visa: your job.