There are 9 US Post Offices in Smith County serving a total of 184,388 residents equating to 20,488 residents per post office. It's estimated that approximately 294,304 packages are handled across the 9 county post offices annually. Smith County is located in the U.S. state of Texas. As of the 2010 census, its population was 209,714. Its county seat is Tyler. Smith County is named for James Smith, a general during the Texas Revolution. Smith County is part of the Tyler, TX Metropolitan Statistical Area as well as the Tyler-Jacksonville, TX Tyler-Jacksonville Combined Statistical Area."