There are 11 US Post Offices in Montgomery County serving a total of 38,526 residents equating to 3,502 residents per post office. It's estimated that approximately 61,492 packages are handled across the 11 county post offices annually. Montgomery County is a county located in the U.S. state of Indiana. As of 2010, the population was 38,124. The county seat is Crawfordsville. The county is divided into 11 townships which provide local services."