when it goes on sale i grab several since the use by dates are pretty generous-i've got one jar open (in the fridge) and 3 unopened in the pantry that are all good until 9/24.
That's actually the best way to take advantage of sales, and if your area still has double and triple couponing on
paper coupons you save the most. With the way inflation raised prices, saving here and there adds up.
This is how it works:
The same items tend to go on sale every 6 to 8 weeks. Some items are rarer at 10 to 12 weeks. When something goes on sale, don't just buy one item. You buy as many as you will use until it goes on sale again. So, if you go through a jar of mayo a week, you'd buy 6 - 8 jars on sale to last you to the next sale. 6 jars of Hellmann's mayo, normally $6, bought on sale at $4 saves you $12.
The real savings are when you COMBINE the sale WITH PAPER COUPONS for the same item. Stores usually don't regulate you being able to use a coupon with an item on sale. (Some places do limit the
amount of coupons able to be used.) Instead, manufacturers and large chain supermarkets actually work together on this. They want you to buy their product over other brands, and hopefully become brand loyal, so they make incentives to get their items. If a mayo coupon is in the Sunday newspaper coupon circulars a particular week, generally, expect that brand of mayo to be on sale at large chain supermarkets in the next/few couple weeks.

Or before the expiration date of the coupon which is about 3 months.
You think, I have ONE coupon for $.75 off one jar of Hellmann's mayo. Big whoop.

Yet, with people recycling their newspapers nowadays, you may be able to get 6 coupon circulars from friends, neighbors or coworkers who still read newspapers and toss them in the clean recycling bin after. $.75 x 6 coupons gives you another $4.50 off the Hellmann's mayo for a total of $16.50 off!
AND there are probably 6 other items in that one coupon circular in which you can combine with other sales. We all use shampoo, toothpaste, laundry detergent, etc. If all those coupons are also $.75 off x 6 items each, that's $4.50 x 6 = $27 in coupons in one circular PLUS the amount off the sale price. NOW collecting those coupon circulars and keeping an eye on the sales may become worth the time.
Also, ironically, do NOT be brand loyal if you can. If you normally buy Tide, but you get great coupons for Persil for a $1 off + the sale price of $3 off, get the Persil (unless you are really opposed to that brand.)
And as I mentioned earlier, if you live in an area that doubles the face value of a coupon, that $.75 coupon becomes $1.50 off instead. Places that triple coupons are even rarer and may be extinct in most places now.
Some drug stores like Rite Aid and CVS also have sales and their own STORE coupon for say, $1 off a sale item that week. They MAY allow you to add the manufacturer's coupon from the Sunday coupon circular onto top for added savings. Store coupons directly from that store, (a Rite Aid coupon for an item,) are
different than the manufacturer's coupons and usually able to be used together, called stacking. (Usually the sale's flyer will list if they do NOT allow the two different coupons to be used together.
Don't worry that the store is losing money by you using coupons. In the fine print, it usually says the store will receive full face value of the coupon plus $.12 cents per coupon for handling.
Due to the popularity of the
Extreme Couponing cable TV show and those people
abusing couponing by buying 20 items in one visit and leaving the shelves empty so no one else could get the item on sale,

many stores now limit the
amount of coupons PER ITEM,
per visit.
And if you use digital coupons instead of the paper coupons, there is likely to be a limit on how many items you can get
per account, like 2-6 of an item.
If you shop at stores that you know are well stocked, and do the
Circle of Life concept, "You should never take more than you give," and leave enough for others, definitely take advantage of buying multiples on sale with coupons. (I'm well stocked up on Folgers coffee, down to $2 per canister, for a while.

)