The earliest recorded on-cover use of an official seal was in Italy in 1864. Many other countries produced their own during the following decade. The United States issued its first post office seal, for use by the Dead Letter Office, in 1877.

Official seals have been recorded from over 150 countries. Seal dimensions range from barely an inch in width on a few Danish examples, to some of New Zealand that are more than five inches wide. Designs vary greatly and include elaborate, beautifully engraved Queen Victoria and King Edward VII portrait seals of Canada and Newfoundland to relatively simple typeset seals from Mexico or Egypt.

A few countries, such as Guatemala and Sierra Leone, have issued just one official seal, while the People's Republic of China has released at least 110 different seals (and counting)! Peru has over 60 recorded types, only a handful of which have been actually seen on cover.

Some seals are scarce, especially from remote or "exotic" places such as Fiji, Macau, or Zanzibar. Because official seals were most commonly used to repair damaged envelopes or cards, most mail items having them were discarded by the recipient due to their condition and have therefore been lost to collectors.

Few countries continue to use post office seals today. Most postal authorities now use tapes rather than labels for repair, or they enclose badly damaged items in plastic bags. The era of government issued seals appears to be ending.

To explore examples of the wide range of officially sealed mails of the world, click on the Country (or section) of your choice in the menu on the left side of this page. Categorization is by the country of seal origin. Issue and earliest known usage dates (EKU) are also listed where possible.

Unless otherwise specified, all reference numbers shown on this site are from Jim Drummond's Official Seals of the World Catalog, 2007 1st edition.

Post Office Seals of the United States and Possessions by Jim Kotanchik Hard bound with dust jacket, 8½" x 11" format. Over 350 pages with 630 color images. Covers all of the Scott-listed seals in great depth with new information on printing data and dates of use. Exhaustive treatment of the typeset seals including probable issue dates and identification of some of the printers. Presents Proofs, Trial Color Proofs, Essays, and Specimens not previously documented. Broad coverage of DLO seals, Carrier Labels, Postage Stamp Agency Seals, Sea Post Seal, Modern US Seals, and the US Possessions including the Ryukyu Islands Seals. Includes valuation guide for every known variety. Winner of "Grand and Gold" award for literature at APS StampShow 2006 in Chicago. Available from the author for US$85 postpaid media mail to US addresses. Postage extra for overseas shipping. PayPal accepted to account shown below. Also available from your favorite philatelic literature dealer. Jim Kotanchik PO Box 684 West Acton, MA 01720-0684 USA e-mail: jimkot@verizon.net