According to fresh data from PWC, U.S. adults will spend, on average, $661 on gifts this holiday season (and an additional $336 and $192 on travel and entertainment, respectively).

Some retailers will do better than others, when the final holiday shopping numbered are tallied up. Amazon, for example, seems primed to prosper from Thanksgiving to New Year's Day. According to data from Trefis, Amazon (AMZN - Get Report) accumulated 27.4% of market share on Black Friday sales, and 30.1% on Cyber Monday sales - well ahead of other competitors.

But does that mean Amazon is offering better deals and lower prices to holiday shoppers? Not necessarily, states LendEDU in a brand new report that ranks the holiday shopping experience with Amazon against one of its chief rivals -- Costco.

"I wanted to find out if it would be cheaper to shop at a brick-and-mortar Costco (COST - Get Report) store or online at Amazon," says Mike Brown, research analyst at LendEDU. "After comparing 38 identical items (and many free samples from Costco) from each place, I was able to crunch the numbers."

Brown produced yeoman's work on the report, personally visiting a Costco in Long Island City, N.Y., snapping photos, and jotting down prices on 38 store items. He later compared the prices of those 38 items with their exact prices on Amazon.

"After all of the data was collected, I was able to run the percentage price difference equation," Brown said. "To do this equation, I first subtracted the Amazon price from the Costco price and then divided that number by the Costco price. Afterwards, I multiplied the resulting number by 100 and that was the percentage price difference."

What Brown discovered may be an eye-opener for retail consumers who swear by

Here are the key findings, according to Brown:

  • If all 38 items were purchased at the exact same time, buying off Amazon would be 12.10% more expensive than shopping at a physical Costco store.
  • On average, Amazon items were 56.48% more expensive than the identical items at the Costco store.
  • The narrowest price difference was with technology products. Beats 3 wireless earphones were actually 21.12% cheaper on Amazon.
  • The widest price difference that favored Costco were food and beverage products that, on average, were 120.15% cheaper at Costco.

"I found that after shopping at a physical Costco Wholesale location and browsing Amazon for 38 identical items, on average, products on Amazon are 56.48% more expensive than the same goods found at the Costco store," Brown says. "Additionally, if a consumer was to buy all 38 items that we analyzed in one fell swoop, he or she would find that the total price from buying on Amazon would be 12.10% more expensive than going to Costco and purchasing the same items."

Costco fans.
Costco fans.

For example, Brown compared the price of an Apple (AAPL - Get Report) 12.9 Inch iPad Pro, where the pricing difference wasn't substantial. At Costco, the price for the iPad was $899.99, while on Amazon, the price stood at $949.25, a 5.47% price differential, Brown reports.

But move over to the grocery products aisle and Costco prices are substantially lower. A case in point: A 250 oz. container of Arm & Hammer Plus OXI Free & Clear washing detergent is priced at $10.99 at Costco, but costs $27.00 on Amazon - a 145.68% pricing difference, Brown notes. Additionally, an 18-count of Dannon Light & Fit Nonfat Yogurt goes for $12.99 at Costco, but costs $37.99 on Amazon - a price percentage difference of 192.46%.

"Both by average price difference and total price difference, the widest price discrepancy favoring Costco Wholesale came from food and beverage products," Brown states. "On average, food and beverage products from Amazon were 120.15% more expensive when compared to the same goods at Costco. The total price of all the food and beverage products from Amazon was 95.82% more expensive than at Costco."

"Judging from these results, consumers would be best served purchasing their food and beverage items from Costco Wholesale instead of on Amazon." Home appliance price differences between Amazon and Costco also tilted in Costco's favor. In terms of total price difference for all home appliances analyzed, shopping on Amazon proved to be more expensive than Costco by 30.06%," Brown says. "In terms of average price difference for home appliances, Amazon products were more expensive than similar Costco items by 39%."

Some product pricing differences really stand out. For instance, the Panasonic Microwave was more expensive on Amazon by 100%, the widest appliance price discrepancy favoring Costco. "On the other hand, the Shark Rocket Flex Ultra-Light Corded Stick Vacuum proved to be the most favorable for Amazon, as it was only 1.33% cheaper than Costco.

As the Shark Vacuum model pricing attests, Costco didn't come out ahead in all 38 product price comparisons. Amazon priced moderately lower on a Dell 13.3 inch Inspiron laptop (an 11% price difference favoring Amazon) and on a set of PowerBeats 3 Wireless Earphones (a 21% price percentage difference favoring Amazon.)

Of course, price isn't everything, and it's fair to point out the flexibility in having an Amazon deliver products right to a shopper's front door.

"One of Costco's core business pillars is cost, while I think Amazon points to their convenience-factor," Brown says. "Amazon can get anything to your house in two days simply by clicking a few buttons. So, in a strictly cost-driven report, Costco wins, but if I had factored in convenience, maybe Amazon would have come out on top." 

The biggest takeaway for shoppers? Don't automatically head to the internet when it's time to shop, Brown advises. "Look at brick-and-mortar places first, and if the convenience of online shopping outweighs the cost by enough of a margin, then head back to your computer, smartphone, or tablet."

Consumers seem to be one step ahead on that sentiment. Their takeaway is a simple and balanced one - take the best that both Costco and Amazon provide.

"For out-of-state holiday purchases, Amazon works best," says Bill Seavey, a retirement consultant and book author in Cambria, Cal. "My wife Eleanor has ordered a half-dozen Amazon gift cards for our out-of-state grandchildren. But she also purchased three Costco gift cards for our children who are local - they'll likely use the cards to buy groceries at Costco since they shop there, already."

That's why consumers should be the biggest beneficiaries of retail titans going toe-to-toe on holiday shopping prices. As prices come down, consumers pocket more cash savings.

"Retailers have been stepping up their game against Amazon this year," says Marcy Comer, vice-president of marketing at, in Austin, Texas. "In recent price comparisons on top tech and fashion items, I saw little to no difference in prices at retailers such as Best Buy, Macy's and Sam's Club versus Amazon."

"But this year we were able to purchase 50 Amazon Echo's for our employees at Dosh at Best Buy for the same price as Amazon and get them the same day. That's something you wouldn't have seen in years past."

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