Furnished Apartments For Rent Williamsport Pa . Start your free search for furnished apartments today. Studio apartments average $550 and range from $475 to $650. 2500 Federal Ave, Williamsport, PA 17701 from www.realtor.com Find your next apartment in williamsport pa on zillow. Apartment rent in williamsport has increased by 12.5% in the past year. This property is for rent.