About a week ago, I was preparing my CVS list, and I realized that I had inadvertently let one of my ECB's expire (by about 5 days). I was aghast...that was the same as throwing away money in my book!
We all make mistakes, so I sucked it up and continued to CVS with the rest of my ECB's. I was going to throw away the expired ECB's, but I decided I would see if they would possibly accept them (since I've heard cases of them accepting them if they are a day or 2 expired).
I was pleasantly surprised when the cashier said yes that she would take the expired ones. So, I asked how long they would accept them after expiry. She said about a month!
Now, I don't know if ALL CVS stores will accept expired ECB's for a month after expiration, but it doesn't hurt to ask your CVS what their policy is.
If you are curious about CVS' coupon policy, you can find that here.