Look closely at the barcode on the coupon. That is what tells the POS (point of sale) computer how much credit to give you. The barcode does not always agree with the printed words. You may be able to save money by using the offer that's encoded in the barcode instead of the wording. Reading the coupon as well as the barcode (while ignoring the pictured item) can save you even more money!
Anatomy of a coupon barcode:
1-22222-33344-5 (6666)7-88888 and possibly 9999
1 - a 5 or 9 (sometimes 99) for mfr coupons (& not followed by 00000). A coupon that starts with a 5 can double, even if it says "do not double" (dnd) on it. A coupon that starts with a 9 will not automatically double, but of course it can be done manually.
22222 - five-digit manufacturer code
333 - three-digit family code; when used with the mfr code, it tells which item(s) the coupon is good on. Often the coupon's family includes many items that are not listed on the coupon, but the POS will recognize them.
A trailing zero digit in the family code is used like a wildcard. A family code of 000 has 3 wildcards, 100 has 2 wildcards, 110 and 010 have one, and 001 has none.
So, if you know that Product Z is in the 146 family, then you could use any of these family-coded coupons on Product Z: 146, 140, 100, 000. If the family code is 000 then the coupon is good on ANY product from that mfr.
Family code 992 is for "no product verification". Technically, the 992 is a message to the *computer* to not verify whether you bought the item. Its intended use is for things that don't fall into a 'regular' family - like '$1 off any Heinz X or Campbell's Y or BallPark Z'. Wine tags are often 992's because if you get to save off *any* seafood, there's no way to know which seafood you will choose, and no other way to encode it.
44 - two-digit value code. This tells the computer how much credit you get for the coupon. The one value code that always raises a flag is 00, which is specifically for checker intervention. No matter what, this coupon will beep - even if it's a 992. Many stores will also flag frees (01) so that the actual price may be written in. There is at least one chain that flags ALL frees, even b1g1f (14), b2g1f (16), b3g1f (19), b4g1f (02). Monga has some really good links here
including a link to the table of value codes. Print this out and keep it in your coupon binder, it's a great reference tool.
Often the value code does not match the printed words. As you look through the table you just printed, you'll notice there are NO codes that require a purchase of more than 4 items. The next time you see a coupon that tells you to buy 6, check the value code - chances are good that you only need to buy 3 or 4 for the POS to give you the credit.
There is no way to encode "buy this, get that free" unless it is in the offer code (see below). Those coupons are encoded as "get that free" (or "checker intervention"). Again, frees may be flagged at your store.
5 - single "check" digit, used by the computer to help it verify that it scanned the barcode correctly.
(6666) - code for which coupon format and/or redemption clearinghouse to use.
7 - additional digit to identify the mfr
88888 - offer code, supposedly for mfr's use. May contain further data about the coupon offer, may be readable by the store. YMMV.
9999 - optional. If it appears, it is the expiration date, coded as MMYY. All coupons expire at the end of the month, there is no way to encode a specific date. Not all stores can read this info.
Keep in mind that different stores may have programmed their POS systems to handle coupons differently. What works at Store X may not work the same at Store Y. It will probably take some experimenting to determine what your store's POS does.