Costco vs. Sam's Club - which one should you join?

HOUSTON -- If you don't mind giant sizes and you have room to store boatloads of things like paper towels, warehouse clubs are a popular shopping option. But how do you decide which to join? Consumer Reports compared the two biggest - Costco and Sam's Club.

Both Costco and Sam's Club promise to save you big bucks, but is one better than the other? Consumer Reports put them head- to-head to find out.

"The first thing we looked at was membership cost. Both offer different levels. Costco starts at

$55, Sam's Club at $45. So not a big difference, but something," said Consumer Reports' Margot Gilman.

In Consumer Reports surveys of subscribers, both clubs consistently get high marks on price. When it comes to services, however, the offerings vary.

At Costco, you can get a mortgage, invest in securities or buy car insurance.

Sam's Club offers online auctions, where you can bid on things like TVs and laptops, starting at just $1. You can also sign up to receive regular shipments of things you use lots of, like diapers or printer ink.

For electronics, Consumer Reports reader surveys find both Sam's Club and Costco have the same quality. However, Costco rates higher for the quality of so many other things, including jewelry, women's and kids' clothing, and eyeglasses.

"We also looked at customer service and neither club has bragging rights here. Costco squeezes ahead by just a little, but readers' scores range from poor to fair," Gilman said.

Not happy with fruit or produce you bought? Sam's Club offers a "double-your-money-back" guarantee on fresh food.

If you have other returns, keep your receipt and either club will take it back, usually for up to 90 days. Sam's Club places a limit on some items, like cell phones of 30 days.

The final verdict? Costco has the edge, but Consumer Reports says both stores are worth their membership fees.

With product selection varying so much from store to store, Consumer Reports says the club that's best for you may be the one that sells what you need the most.

Before joining, Consumer Reports suggests checking the products and services offered by each by visiting the clubs' websites and walk-in stores nearest to you.