What You Need to Know About Big Box E-Tailers

1. No jockeying for parking, no mega cart. BJ’s Wholesale Club (www.bjs.com), Costco Wholesale (www.costco.com) and Sam’s Club (www.samsclub.com) match the low prices at their brick-and-mortar stores. That saves you the hassle of finding a space in a crowded parking lot on Saturday morning. Plus, you can use online tools to pull up previous orders and create shopping lists.

2. Membership has its privileges. For $45 a year, you can become a member of BJ’s Inner Circle; a Gold Star or Business membership at Costco is $50; and Sam’s Club charges $40 for new Advantage members. (Nonmembers may buy items online if they pay surcharges ranging from 5% to 15%.) And all three extend their rebate programs for top-tier memberships to online purchases. A BJ’s Rewards membership ($80 a year) entitles you to a 2% rebate on all purchases, up to $500 annually. Costco’s $100-a-year Executive members also earn a 2% rebate, up to $500. Sam’s Club Advantage Plus members ($100 a year) earn a tiered rebate, up to 2%, on purchases worth up to $1 million per year.

3. The Web is an even bigger box. A warehouse club’s Web site typically carries 80% more products than the local store does -- though not the perishables, such as bananas and salad fixings. BJ’s specializes in consumer goods. Sam’s Club caters to entrepreneurs by providing special supplies for small businesses. Costco’s strategy is to provide an inventory of high-quality products and eclectic items, such as a man-size safe from Cannon ($850 including shipping). Prices usually reflect what you’d pay in the club’s store, plus shipping costs.

Subscribe to Kiplinger’s Personal Finance

Be a smarter, better informed investor.

Save up to 74%

Sign up for Kiplinger’s Free E-Newsletters

Profit and prosper with the best of expert advice on investing, taxes, retirement, personal finance and more - straight to your e-mail.

Profit and prosper with the best of expert advice - straight to your e-mail.

Sign up

4. You can stock up discreetly on products that you’d rather not be seen carting out of a store in large quantities. For example, Costco sells prescription drugs online (it’s the only one of the Big Three that does). In a survey of pharmacies in 2008, Consumer Reports found that Costco had the cheapest prescription prices. Costco also sells wine online (in fact, the store is the world’s biggest retailer of Dom Pérignon champagne). The catch? Costco.com delivers wine only to addresses in California, New Mexico, Oregon and Washington.

5. No coupons required. Each warehouse-club site has a section for items that are on sale that day -- no coupon necessary. Among recent offers that beat other top online deals by at least $100: a 47-inch Philips flat-screen HDTV ($998 at BJs.com, shipping included) and a Reebok CrossWalk treadmill ($600 at Costco.com, including shipping). The member coupons you receive in the mail may also be used online.

6. But watch out for the shipping. Unfortunately, the sites don’t tell you how much shipping will cost before you add an item to your online cart. “Shipping costs add to the confusion about shopping online at warehouse clubs,” says Michael Clayman, editor of industry newsletter Warehouse Club Focus. But some sale offers -- with or without a coupon -- waive the shipping. Larger items and more-fragile products may cost more to send. If you don’t like the price, you can cancel the transaction at checkout. As is usually the case with online shipping, you’ll save if you’re willing to wait for delivery.