are-you-saving-money-by-buying-in-bulkA tip I often read in “Save 50 percent off your grocery bill!” types of articles is to buy in bulk. The article might suggest buying a 50-pound bag of rice, a whole butchered cow, or a year’s supply of toilet paper. Is this saving money?

There are certainly times when it makes sense to buy large quantities of certain products. However, you need to be strategic about it. For instance, it would take a couple of years for my family to go through a 50-pound bag of rice. And while I love the warehouse clubs, I’ve learned through trial and error that their mega-sized packages are not always a good deal for us.

Here are some questions to ask yourself before buying in bulk:

Is it a really great buy?

To answer, you need to know the customary price—and the best sale price at your regular grocery store—for things you usually buy. I keep a price list of groceries and sundries our family buys all the time so I’ll know when something is a great deal. For instance, toilet paper at the warehouse club is usually much cheaper than even the store brand at our favorite grocer, so that one is a no-brainer: I buy it in bulk at the warehouse club. On the other hand, our favorite brand of soup is sold in large quantities at the warehouse club—but I can usually buy it cheaper, on sale with a coupon, at my neighborhood grocer.

And I should mention that “buying in bulk” doesn’t have to mean buying large packages at the warehouse club. I’ll buy half a dozen tubes of toothpaste at our nearby grocery store when it’s on a really great sale. Since toothpaste is small and nonperishable, it’s easy to store in our basement.

Can you store it easily?

It’s easy to go overboard when you see a great sale. I know a couple that stores toilet paper under their bed because they don’t have enough room for it elsewhere. If you can store bulk buys creatively, kudos to you. But if your stockpile is getting in the way of your kids’ play areas, or if you have to move it every time you get something from your basement shelves, rethink how much you’re buying. My personal rule of thumb is to buy as much of a particular item as our family will use in about three months.

Is it nonperishable, or can you use it before it spoils/ expires/ your family tires of it?

A while back, I went crazy during a cold-cereal sale. I don’t know what I was thinking: Our family doesn’t even eat all that much cold cereal! After about nine months, it was clear that we weren’t going to use all I bought, so the extra boxes went to a food drive. The next time cereal went on a rock-bottom sale, I bought two boxes instead of 10.

On another note, coffee beans are a good deal in two-pound plus bags at our warehouse club, but I’m finicky about the freshness of my coffee and never used it all before it started to taste “off.” An alternative, of course, would be to split the coffee or other perishable purchase with another family. I know some folks who do that with meat: They buy a side of meat from a local butcher, have it cut up and packaged, then split the proceeds. But when it comes to coffee, I find I’m happy to buy it fresh, in smaller quantities, from my favorite local roaster.

Is it something you’ll use over a long period of time?

Party supplies are an example. I always appreciate having extra napkins, plates and plastic cutlery on hand. We use them for birthday parties, holidays, block parties—you name it. When my kids were younger, we also bought diapers in bulk whenever we hit a good sale. Some other items that are great to buy in bulk include bar or liquid soap, laundry detergent, food storage items (foil, wraps, storage bags), razors, shampoo/conditioner, toothpaste and toothbrushes, paper products, batteries, bottled water, and other canned/bottled drinks. When it comes to food, I suggest buying only as much as you’ll use in three to four months. Be sure to watch out for expiration dates, store items as suggested so they don’t spoil, and put your oldest food items toward the front of your pantry or freezer so you use them first.

Teri Cettina is a mom of two daughters and freelance writer who specializes in personal finance and parenting topics. She blogs at Your Family Money. Follow her on Twitter: @TeriCettina.