The Post Mark Collectors Club (PMCC, for short) is a U.S.-based 501(c)(3) nonprofit organization dedicated to the study, acquisition and preservation of postmarks, postal history and related items; and to the research, recording and preservation of post office history and its attendant ephemera. More importantly, it's a community with hundreds of dedicated members (primarily across the United States). We are a premier nonprofit affiliate of the American Philatelic Society.
The PMCC maintains a host of valuable and unique resources, including the world's largest museum dedicated to postmarks (with approximately two million philatelic items in all), at Historic Lyme Village in Bellevue, Ohio. The organization maintains the most accurate directory of U.S. post offices available, as well as the world's most expansive curated collection of post office photographs. We also host an annual convention, located in a different part of the country each year!
Joining the PMCC yields many benefits. Members gain access to closed philatelic auctions, pay members-only prices for new post office Directory listings, and receive the 11-issue-a-year PMCC Bulletin.