A Canadian postal code () is a six-character string that forms part of a postal address in Canada. Like British, Irish and Dutch postcodes, Canada's postal codes are alphanumeric. They are in the format A1A 1A1, where A is a letter and 1 is a digit, with a space separating the third and fourth characters. As of October 2019, there were 876,445 postal codes using Forward Sortation Areas from A0A in Newfoundland to Y1A in Yukon. Canada Post provides a postal code look-up tool on its website, via its mobile application, and sells hard-copy directories and CD-ROMs. Many vendors also sell validation tools, which allow customers to properly match addresses and postal codes. Hard-copy directories can also be consulted in all post offices, and some libraries. When writing out the postal address for a location within Canada, the postal code follows the abbreviation for the province or territory. History City postal zones Numbered postal zones were first used in Toronto in 1925. Mail to a Toronto address in zone 5 would be addressed in this format: 37 Bloor Street West Toronto 5, Ontario As of 1943, Toronto was divided into 14 zones, numbered from 1 to 15, except that 7 and 11 were unused, and there was a 2B zone. Postal zones were implemented in Montreal in 1944. By the early 1960s, other cities in Canada had been divided into postal zones, including Quebec, Ottawa, Winnipeg and Vancouver as well as Toronto and Montreal. For example, an address in Vancouver would be addressed as: 804 Robson Street, Vancouver 1, B.C. In the late 1960s, however, the Post Office began implementing a three-digit zone number scheme in major cities to replace existing one- and two-digit zone numbers, starting in Montreal, Toronto and Vancouver. For example, an address in Metropolitan Toronto would be addressed as: 1253 Bay Street Toronto 185, Ontario Toronto's renumbering took effect 1 May 1969, accompanied by an advertising campaign under the slogan "Your number is up". However, with impending plans for a national postal code system, Postmaster General Eric Kierans announced that the Post Office would begin cancelling the new three-digit city zone system. Companies changed their mail addressing at their own expense, only to find the new zoning would prove to be short-lived. Planning As the largest Canadian cities grew in the 1950s and 1960s, the volume of mail passing through the country's postal system also grew,