Grocery bill got you down? Read on to find out Wise Bread's smart strategies for supermarket shopping.

Here's the excuse I hear most often for why people don't grocery shop frugally. Say it with me: "I don't have time."

Lack of time is not only the most common hurdle, it's also the easiest to overcome. The fact is, you can save money on groceries without spending more time shopping. In fact, you can probably cut down both the money you spend and the time you spend shopping, by changing one thing: your technique.

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Maybe you didn't think picking up food for dinner as something that needed technique. You were wrong. There are dozens of techniques for filling the fridge, but some of them are better than others. Here are the five smartest.

1. Periodically "Eat Down the House"

Why it's smart: Prevents food waste, which saves money. Keeps cupboards, fridge, and freezer uncluttered, which saves you from wasting time searching for things.

This first technique doesn't actually involve stepping into a grocery store. Eating down the house simply means that you use up the food you have already purchased. Often people don't even know what they've got in their pantry or deep freeze. Take some time to take stock. Use your creativity to come up with some recipes making use of what you have — or consult a website like SuperCook, which tells you what you can make with what you have on hand. (See also: Fancy Ways to Use Leftovers)

This technique will not only set the stage for future savings, but it will also save you time and money during the week you're doing it, because you simply won't have to go to the store (or only to pick up a few fresh supplements to what you have on hand).

2. Set a Budget and Stick to It

Why it's smart: Like all self-improvement efforts, nothing succeeds like setting and working toward specific goals. Without a budget to measure against, shoppers have no idea whether they're shopping frugally or not. This also saves time because once you have figured out how many groceries you use in a typical week, you're more likely to get them all at once and not make multiple trips. (See also: 20+ Ways to Lower Your Grocery Bill)

When I used to post my weekly grocery spending every single week, I got lots of comments from the peanut gallery. Some thought my budget — whether it was $80 a week or $120 — was too easy to attain, while others thought it was unrealistically low. The number you set as your weekly budget has absolutely nothing to do with what anyone else thinks. It's a goal for you to aim for each week.

If you want to save money, first keep all your receipts to measure how much you spend on groceries for several weeks. Once you have a weekly average figured out, cut 5 percent from that amount. Practice for about a month to see if you can stay under that goal. If it feels easy, go ahead and cut it another 5 percent. Keep doing this until you get to a point where you still feel challenged, yet you're not feeling deprived. Don't forget to bank the savings!

3. Rotate Grocery Stores

Why it's smart: The same items sell for wildly different prices at different stores on different weeks. By periodically visiting different stores, you can reap the savings of all stores without having to waste time visiting multiple stores each week.

Each week, most stores will feature a few items that are out-and-out steals. And different types of store offer different types of savings. If you had unlimited time, you could visit multiple major chains and pick up their deals of the week, stock up on produce at a low-cost ethnic market, hit Aldi for everyday low-priced staples, and visit Costco for dog food and diapers. But at that point, shopping would be your full time job, and no matter how much you save, you can't save enough to make up for spending that much time.

Instead, work all your favorite stores into a rotation. When the weekly grocery ads come out, look each one over and decide if the deals are compelling enough to make that store your destination this week. If so, stock up on the sale-priced items and enough other reasonably good deals to get you through the week. On weeks that the deals in the ads don't excite you, hit an everyday low prices store like Aldi or a warehouse store instead. (See also: Things You Should Buy at Costco)

4. Grab Discounts

Why it's smart: Grocery discounts may seem like only a few cents here and there, but when looked at in terms of percentages, they can add up to a good 20 percent cost reduction. Spending 20 percent less is at least as good as getting a 20 percent return on investments — but savings are tax free.

Beyond the regular advertised sales, there are lots of ways to get discounts on groceries if you keep your eyes open. Coupons are one way, of course. Also keep your eyes peeled for marked-down perishable goods; for instance my local Safeway puts out meat and deli items reduced 30 percent to 50 percent every day. Not all stores do this, but when you find one that does, work it into your regular rotation.

Some stores offer discounts through online programs now. Safeway promises 20 percent or greater savings to users of its Just for U program, and personally I have saved even more by using it.

5. Combine Deals

Why it's smart: Taking advantage of multiple promotions yields maximum savings.

This is the most challenging part of grocery savings, but it can also be the most fun. Say you have a coupon for your kids' favorite cereal. The coupon only brings the price of the cereal down to match the store brand, so you might wonder if using coupons is even worthwhile. Well, it's not very worthwhile — if the item you're buying isn't also on sale. Hold onto that coupon for a week or two, until the cereal goes on sale, and then you're combining two deals — and likely beating the price of the store brand.

Other ways to combine discounts is to look for Catalina promotions, which print out rewards after you make a purchase, or add a "basket coupon," which takes money off when you spend a set amount on your whole purchase. When advanced bargain shoppers brag that they got groceries for free, or even made money on certain items, they're usually combining multiple deals.

—Carrie Kirby

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