There are 37 US Post Offices in Monroe County serving a total of 601,251 residents equating to 16,250 residents per post office. It's estimated that approximately 959,664 packages are handled across the 37 county post offices annually. Monroe County is a county in the western portion of the state of New York, in the United States. The county is along Lake Ontario's southern shore. As of 2013, Monroe County's population was 749,857. Its county seat is the city of Rochester. The county is named after James Monroe, the fifth President of the United States of America. Monroe County is part of the Rochester, NY Metropolitan Statistical Area."