Mobile Post Office Society

Streetcar RPO Airmail Cover (Ex-Truax)

Mobile Post Office Society (MPOS) was founded in 1950 by a group of philatelists interested in the study of United States Highway Post Offices. It soon expanded to focus on Railway Post Offices, and eventually to the enroute distribution and postmarking of mail all over the world. It is a nonprofit organization, affiliate #64 of the American Philatelic Society.

MPOS has published the definitive studies of postmarks from the Railroad, Station, Route Agent, and Messenger services, and the Railway, Highway, Streetcar, Terminal, and Air Mail Field Post Offices as well as the Transfer Offices and Clerks in United States philately. Most recently, MPOS has added a focus on the USA's Rural Free Delivery (RFD) service and postmarks that were used around the beginning of the 20th century. 1996 saw the start of a study of "TRANSIT" markings used at intermediate Post Offices.

The research and work of many years culminated in the completion of the "United States RPO Postmark Catalogue", begun by the late Charles Towle, and completed through the efforts of MPOS Past President Fred MacDonald, along with the work of many dedicated philatelists.

MPOS publications are available for purchase by interested philatelists, whether or not they are members of MPOS. Current members receive all benefits of membership including a subscription to Transit Postmark Collector and MPOS serial publications; Sustaining and Patron members enjoy the serial publications and extra publications at no charge, plus price reductions for all literature. Sustaining and Patron members also get the satisfaction of knowing that they support an organization of dedicated, like-minded philatelists and its scholarly research, as well as its fun activities and show participation.

Annual dues for membership in MPOS are $23/year for "ordinary" membership which includes a subscription to "Transit Postmark Collector," the journal of MPOS which is currently in its 47th year of publication. "Sustaining" membership is available for $38/year, which includes an additional publication per year at no extra charge. "Patron" membership is $53/year which includes two publications and an extra discount on literature. "Family" membership is available for an additional $5/year. A dues discount of $3 is offered annually to early payers. Part of the dues for "Sustaining" and "Patron" membership can be considered to be a tax-deductible contribution to MPOS, and all outright contributions to MPOS are tax-deductible.

 MPOS Show and Meeting Calendar

 MPOS Books and Literature Pricelist
Note: This is the new MPOS literature pricelist as of December, 2008. Please note the new address for literature orders. EMAIL ADDRESS SHOWN IS INCORRECT - it should be tompost48@gmail.com. MPOS Members get a discount from list prices as shown at the end of the pricelist.

The price of a "complete" RPO catalog as of December, 2008 is $110.00 to non-members, appropriate discounts to members.

  Auction of Bob Truax' Streetcar RPO Covers

 MPOS Press Releases

 Overseas Members Only - Dues Payments via Paypal
Please make payments to dnc@math.uga.edu to ensure proper credit of dues.

  Our Treasurer, Nancy Clark was awarded the American Philatelic Society's highest award, the Luff Award in July, 2008. Read about it at
the APS Web Site stamps.org

 Nancy Clark's May 2009 APS Magazine article on commercial HPOs

Click for a Printable MPOS membership application. You may also write to Doug Clark, PO Box 427, Marstons Mills MA 02648.

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Contents of this page are © copyright Rick Kunz 2011. All rights reserved. Publication, reprinting or other redistribution of the material contained herein is prohibited without the express written consent of the author.