Tower Health on said Tuesday that it will acquire Premier Urgent Care's 18 Philadelphia-area locations in a deal that is expected to close later this fall.

Following the purchase, Tower Health, of West Reading, Pa., will become the largest provider of urgent-care services based on weekly visits, in the Philadelphia region, the nonprofit said in a news release.

The purchase price was not disclosed. Premier employs more than 200.

Edward M. Silverman, who founded Premier in 2006, will work on contract for Tower Health and "will provide an executive leadership role for a prescribed period of time," said Clint Matthews, Tower's president and chief executive.

There were signs of financial duress at Premier, which has millions in federal tax liens outstanding, according to recent court filings by the Pennsylvania Department of Revenue and the IRS. Three federal liens total roughly $3.95 million and one state lien totaled just over $16,000.

Tower Health purchased Premier's assets, but didn't assume any of the tax liens in the deal, Matthews said.

Asked about how the deal came to fruition, Matthews said, "It was a mutual overture. I didn't know him, but our staff knew about the operation itself and knew of the locations. This was an area of interest we wanted to more fully develop," he said. "We were able to acquire rather than start new sites," he said.

It "can make great sense for a health system to acquire urgent-care centers that are up and operating — especially if the price is right," said Stuart Fine, professor of health services administration and policy in the College of Public Health at Temple University. "There are costs associated with starting any enterprise from scratch, and those start-up costs can be reduced or eliminated by acquiring going concerns."

Tower entered the Philadelphia market last year with the purchase of five hospitals from Community Health Systems Inc. for $418 million. Those hospitals (Brandywine Hospital in Coatesville; Chestnut Hill Hospital in Philadelphia; Jennersville Hospital in West Grove; Phoenixville Hospital in Phoenixville; and Pottstown Hospital in Pottstown) have some overlap with the Premier locations, giving Tower a chance to deepen its reach.

A 19th Premier Urgent Care location is scheduled to open soon in Conshohocken, Tower said.

Tower, which last week announced a joint venture with a subsidiary of Tenet Healthcare Corp to acquire and build ambulatory surgery centers in Southeastern Pennsylvania, also has a deal with  UPMC Health Plan to sell health insurance in nine eastern Pennsylvania counties, but not in Philadelphia.