There are 9 US Post Offices in Putnam County serving a total of 100,321 residents equating to 11,147 residents per post office. It's estimated that approximately 160,124 packages are handled across the 9 county post offices annually. Putnam County is a county located in the U.S. state of New York. As of the 2010 census, the population was 99,710. The county seat is Carmel. Putnam County formed in 1812 from Dutchess County and is named for Israel Putnam, a hero in the French and Indian War and a general in the American Revolutionary War. Putnam County is included in the New York-Newark-Jersey City, NY-NJ-PA Metropolitan Statistical Area. It is located in the lower Hudson River Valley. Midtown Manhattan is around a one-hour drive, and Grand Central Terminal is approximately 1 hour, 20 minute train ride from Putnam County. Putnam County is increasingly considered part of Downstate New York as the New York Metropolitan Area continually increases size. It is one of the most affluent counties in America, ranked 7th by median household income, and 47th by per-capita income, according to the 2012 American Community Survey and 2000 United States Census, respectively."