"The term "snail mail" appears as early as 1942 in the headline of a news article about slow mail delivery.
[3] The term also appears as a sub-headline in a 1951 news article.
[4]
The term
snail post has much earlier usage, as in an article published 1843, in
Fraser's Magazine for Town and Country (page 656).
[5] This was a humorous British reference to the German 'Schnell (fast) Post', which was notoriously slow.
The term
snail mail was used by the
U.S. Post Office in magazine advertising in the mid to late 1960s to encourage use of
zip codes. Ads for zip code use appeared in many issues of
LOOK,
Life, and the
Saturday Evening Post magazines and displayed a caricature of a large snail outfitted as a letter carrier, with the term "Snail Mail" in bold lettering.
[6]
The term appears in a
Russell Baker humor column about the slow speed of the U.S. Postal Service in 1969"
Nailed it!