H.B.
I don't think that most cashiers even look at the date. It wouldn't hurt to try it, all they can do is tell you no. Walmart usually has the best price on Similac. Another thing I did was to re-register on the similac website. They stopped sending me the checks after about 6 months so I just signed up again and they started sending them again. You can sign your relatives up too and they can pass the checks on to you. My MIL did this for me. You can also try Ebay...they always have a ton of checks and coupons on there. I've sold some myself. It doesn't matter whose name is on the checks. Also when your daughter gets 9 months old you can switch to the second stage formula which is a lot cheaper. $18 vs $26 a can.