From an article I found on postal codes worldwide...
CANADA: Canadian postal codes do indeed invariably consist of two setsof three characters separated by a space, and the sequence is invariably ANA NAN [a mnemonic worth remembering!], where A=alphabetical and N=numerical. The first character indicates geographical location, moving east to west (eg Nova Scotia postal codes begin with B; Manitoba with R, British Columbia with V). The two largest cities in Canada, Quebec and Toronto, have their own prefixes (H for Quebec, M for Toronto).
There doesn't seem to be a useful way of remembering Canadian postal codes. Writes one respondent:
When the system began there were merry ads telling us to invent our own mnemonics, and some people did, with sequences that made that possible. But what can I do with mine, which are M4V 1H1 (home) and M5S 1J7 (office)? One tends to learn them rhythmically, like nonsense rhymes, and nobody I know can remember more than a few. The one advantage of this system is that because no one can really remember a lot of them, one is constantly CHECKING, and this leads to improved
accuracy.
Logic worthy of a Little ***** joke.
Some Canadian respondents suggest that their postal codes aren't that bad, though all agree they have no logic beyond the first letter and that they are hell on wheels to remember. Says another [American,admittedly] respondent:
Somewhere there has got to be a book delving into the intellectual background of the UK-Canadian system; it must have some bizarre rationale in an offbeat theory of info organizing. If you ever find the name & picture of the man who created it, publish these so we can all mock & dishonor him. My Canadian friends, to a person, say that no one in Canada bothers with the postal codes; they all hate them and ignore them.
http://palimpsest.stanford.edu/byform/mailing-lists/exlibris/1996/05/msg00254.html
(noticing the little stars above I am wondering why the word m.o.r.o.n is a censored word? LOL)