Amazon (AMZN) - Get Report and Walmart's (WMT) - Get Report Jet.com are kicking their appliance sales into full gear, and Sears best be on high alert.

"Over the last several months, we have seen Amazon and Jet.com expanding their appliance offering, which could create a growing risk to Home Depot, Lowe's and others," BMO Capital Markets analysts Wayne Hood, Brian Welsh and Steve McManus said in a research note Tuesday. They warned that Home Depot (HD) - Get Report and Lowe's (LOW) - Get Report "will have to keep their pencils sharpened" to keep up with the lower prices they are already seeing on certain appliances from Amazon and Jet.

"We would become increasingly concerned if Amazon and Jet widened their assortment, offered free delivery and installation services, bundled offers and special buys and developed strong financing options," Hood, Welsh and McManus added.

Dying Sears Holdings Corp. (SHLD) -- which is still greatly reliant on appliance sales and installation services -- should be more petrified of Amazon's and Jet's efforts in the category. 

"We have seen Sears' appliance offering start to decrease over the past few months," Hood, Welsh and McManus said. "In the categories we track, Sears' offering has dropped to 1,600 appliances from 2,002 in January. Our data suggests Sears is carrying less General Electric (GE) - Get Report and Samsung branded appliances as well as refrigerators." With Sears offering fewer choices to appliance shoppers, the struggling retailer could easily give away business to the hard-charging Amazon and Jet.

Losing in appliances has become the new norm for the one-time category leader Sears, however.  

In 2015, Sears' market share in appliances fell to 19%, pushing it to number three on TWICE Magazine market research partner The Stevenson Company's list of the top 50 appliance retailers, just under Home Depot. In 2014, the retailer managed to retain the number two spot, below Lowe's which pushed Sears out of the top slot three years ago. At one time, Sears had a 40% share of the appliance industry.

Twice senior editor Alan Wolf told TheStreet Stevenson's 2016 data on appliance sales will be released on June 5, but predicted that the results will likely be brutal for Sears.

"Based on successive same-store sales declines in appliances in Sears Holdings' quarterly earnings reports, and round after round of store closures, I don't think it's a stretch to project that Sears' namesake retail chain will show another sales decrease for calendar year 2016," Wolf said.

As well as less choices, Sears' financial struggles may have it trying to charge too much for appliances vs. rivals. Moreover, Sears has been besieged on social media in recent years with complaints from consumers about appliance quality, customer service and installation processes (see example above).  

In April, BMO found that a basket of appliances at Sears was 7.8% higher in price than an identical basket at its home improvement peers, compared to in January, when it was only 2.5% more expensive.

Sears Holdings Corp. spokesman Howard Reifs didn't return a request for comment. 

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Editor's Pick: Originally published May 23.

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