More than 100 million people now shop at Sam's Club, Costco and BJ's, in hopes of finding the lowest prices on items from tires to tiaras, cameras to crackers.
Here are a few tips to help you brave the masses and navigate the aisles in search of the best bargains.
Tip One: Look for Special Price Coding
Warehouse stores have special price codes for clearance items.
"If it ends in .97 at Costco it's on clearance and it's not going to be restocked," savings expert Julia Scott of bargainbabe.com said.
Price tags that end with a penny at Sam's Club means the item is on clearance.
"So what that means is if you want it, you better get it now," Scott said. Plus it's a good way to scan all the clothing piles and quickly distinguish the best deals.
Tip Two: Electronics
Large electronic stores can charge customers up to 15 percent to restock a returned item. But most membership stores have a 90 day return policy with no fee. BJ's has a shorter window returns, for example computers must be returned within 14 days.
Another incentive for customers to purchase electronic items, Costco and Sam's Club offer free phone-based tech support.
A manager at Sam's Club clued us in to the fact that you don't even have to buy your gadgets at Sam's and they'll still try to help you. You can call 24 hours a day, speak in English or Spanish, and they'll help you navigate your tech trouble.
Tip Three: Luxury Items and Prescriptions
Scott says prescription medications are cheaper too. At Sam's Club there are hundreds of prescriptions that cost $4 a month to fill. At Costco customers do not need a membership to use their pharmacy.
If you want to avoid paying the $40 or $50 annual fee, pay a friend to buy you a warehouse club gift card. Then you can shop to the card limit without paying any surcharges.
Tip Five: Old Reliable Items
Gas is generally five to 10 cents a gallon cheaper than at a local station.
Diapers and meat products are also less expensive. In fact the rotisserie chicken at Costco is so popular it has its own Facebook site.
One word of warning, avoid the middle of the store and the ends of the aisles where they usually put the tempting items you do not need. Instead stick to your list.