I do not know the answer. I had some that would expire the week I thought I was going to need it. Sent note to Camelot but they never responded. Then didn't need it so never followed up. Before that shipment had never seen the expiration date shown before ? Have you ? Good question.
On many things expiration dates can be extended a bit past the manufacturers suggestions as long as the product has been stored correctly but I have not tried this myself with semen extenders. After a conversation with a friend the other day I got curious.
Minitube puts a date on theirs but I am not sure about all others currently.
Am also wondering if the frozen ones have more time extension than those just stored in the frig?
Will eventually check with the sellers but am just wondering about "consumer reports"
I'm pretty positive that Camelot once told me that the extender is good for at least a year in the freezer. You should call them and double check on that though.