Amazon Prime Day vs Black Friday: 1 out of 3 items cost more

Amazon is gearing up for its annual Prime Day on July 16, but getting a deal that matches Black Friday prices isn't a certainty. 

About 30 percent of products are likely to be as expensive or even pricier than on Black Friday, estimates Phil Dengler of BestBlackFriday.com, a website that tracks deals on November's Black Friday. The estimate is based on BestBlackFriday.com's tracking of Amazon Prime Day deals since the shopping holiday started in 2015. 

Amazon (AMZN) created the event as a way to spark interest in its Prime membership, which comes with an $119 annual fee. The idea is to offer limited-time sales for its Prime members, potentially attracting consumers to sign up for the membership. While good deals will be available, it's important to research before buying, Dengler said. 

Last year, Prime Day prices were better than Black Friday prices 76 percent of the time, about on par with 2016, Dengler said. He said he expects at least 70 percent of Prime Day prices will be lower than on Black Friday this year, which means there's about a one-in-three chance consumers could get a better deal if they wait a few months. 

"We always recommend doing your research," he said. BestBlackFriday.com will be tracking prices on Monday and comparing them with Black Friday deals. Dengler also recommended that consumers check CamelCamelCamel, an Amazon price-checker, to ensure they're getting a good deal. 

Amazon's prices may not even be lower than the everyday prices found at rival retailers, according to 2017 research. Walmart (WMT), for instance, tends to sell electronics for 3 percent less than Amazon, according to an analysis last year for CBS MoneyWatch by retail technology firm Boomerang Commerce. 

The best bets for 2018's Prime Day are Amazon's own devices, Dengler said. It's likely that products such as its Kindle Paperwhite are going to be steeply discounted, possibly providing the cheapest deals of the year. Amazon is also likely to discount electronics, TVs and clothing, he added. 

Prime members who want to keep on top of deals should consider downloading Amazon's app, Dengler said. Some of the more competitive deals could sell out within minutes, and the app can help consumers keep tabs on upcoming deals, he said. 

Additionally, Prime members who live near a Whole Foods may want to take advantage of a new offer this year, Dengler said. Shoppers who spend at least $10 on a single purchase at Whole Foods between July 11 and July 17 will receive a $10 credit to spend on Prime Day.