
whose mandate is to ensure the safe, efficient and orderly evolution of international civil aviation.
ICAO has its headquarters in Montreal. Created in 1944 and operational in 1945, it has grown to an organization with over 180 Contracting States. ICAO's aim is the safe and orderly development of all aspects of international civil aeronautics. It provides the forum whereby requirements and procedures in need of standardization may be introduced, studied and resolved.
On June 1, 1955, the Canadian Post Office issued a 5 cents stamp designed by Walter Lohse to commemorate ICAO's tenth anniversary.
A web site dedicated to the postal history of the IACO can be found here.
Essays and Proofs

National Archives of Canada
Approved Model

National Archives of Canada
Progressive Die Proofs

National Archives of Canada

National Archives of Canada
Die Proof

National Archives of Canada
Created 20 January 1955


Overseas Mailers







Domestic Forward Letter
5 cents forward letter rate

Gander to St. John's, August 2, 1955
5 cents forward letter rate + 20 cents registration fee

St. John's Receiver, August 3, 1955
U.S. Surface Letter

Vancouver to Santa Monica, June 19, 1955
5 cents US surface letter rate
U.S. Acknowledgment of Receipt


Registered Mail from Dawson Creek to Los Angeles, June 2, 1955
Acknowledged by addressee, June 7, 1955

Los Angeles, June 7, 1955
UPU Surface Letter

Toronto to Prague, Czecholovakia, August 11, 1955
6 cents UPU surface letter rate
Handling of the letter in Czechoslovakia : non-admissible and returned
The envelope was opened by currency control which deemed the letter non-admissible, sealed the letter and returned to the sender.

Czechoslovakian currency control sealing tape

"Non admis" label
Handling of the returned letter by the Canadian Post Office : Returned with charge

Toronto to Prague, Czecholovakia, August 11, 1955
6 cents UPU surface letter rate
Handling of the letter in Czechoslovakia : non-admissible and returned
The envelope was opened by currency control which deemed the letter non-admissible, sealed the letter and returned to the sender.

Czechoslovakian currency control sealing tape

"Non admis" label
Handling of the returned letter by the Canadian Post Office : Returned with charge
Letters with return addresses returned by foreign countries other than Great Britain, Republic of Ireland, United States, Mexico, and Columbia, were not directly returned to the writer but were returned through the Undeliverable Mail Office (UMO) subject to a charge of 5 cents.

The returned letter was sent to the Montreal UMO
Montreal UMO No. 14 handstamp, September 30 ,1955

Montreal UMO 5 cent charge handstamp
International Air Mail

Toronto to Penzance, October 17, 1955
15 cents one-half ounce air mail rate to Great Britain

Nairn Centre to Jyvaskyla, Finland, June 29, 1955
15 cents one-half air ounce air mail rate to Finland