There are 6 US Post Offices in Lamar County serving a total of 15,574 residents equating to 2,596 residents per post office. It's estimated that approximately 24,858 packages are handled across the 6 county post offices annually. Lamar County (formerly Jones County and Sanford County) is a county of the U.S. state of Alabama. As of the 2010 census, the population was 14,564. Its county seat is Vernon and is a prohibition or dry county. Its name is in honor of Lucius Quintus Cincinnatus Lamar, member of the United States Senate from Mississippi.