The company that made the jingle "Why buy a mattress anywhere else?" famous will be opening three stores in the Tri-Cities soon.

Sleep Country USA is purchasing all 14 Mattress Outlet stores, including two in Kennewick and one in Richland.

The transition from Mattress Outlet to Sleep Country will begin soon, with the hope of finishing the change by the end of the year, said Mike Estes, Sleep Country regional vice president.

Sleep Country, which is celebrating its 20th anniversary, is buying the stores from Mattress Outlet owner Ken Mullinax, expanding the chain into Eastern Washington and western Idaho.

"We are really excited," Estes said. "This has been something we had our eyes on for quite some time."

The stores at 81 Columbia Point Drive in Richland and 231 Vista Way and 908 N. Colorado St. in Kennewick will receive face-lifts, with new carpet and new paint, to have Sleep Country's matching decor, he said.

The company, which already has stores in Washington and Oregon, intends to keep current employees and add some positions, although the exact number of new jobs has not yet been determined, Estes said.

Sleep Country will open two warehouses to supply the 14 stores, one in Kennewick and another in Spokane.

The Kennewick and Richland stores will continue to carry Serta and Tempur-pedic brands, but also will have Simmons, Sealy and Stearns & Foster mattresses, Estes said.

The stores also will offer free same-day delivery, free setup and removal, a 100 percent money back guarantee and a 100-night comfort guarantee, he said.

Estes said Sleep Country also will start its Foster Kid program locally, where the company has drives for foster children, collecting items such as school supplies, pajamas, coats and toys.