Annam and Tonkin were the names of two areas in southern Vietnam that were French Protectorates from the mid-late nineteenth century. Together, Annam and Tonkin used specially overprinted stamps for a short time that are of interest to collectors today.
From 1888, stamps of the French colonies were hand-stamped ‘A & T’ with a value (in centimes). Overprints were in bold black ink. The stamps themselves were from 1881 and 1886; they are ordered by philatelists by their overprinted value and the value of the original stamp (i.e., 1c on 2c, 1c on 4c, et cetera). The most valuable Annam and Tonkin stamp by far is the 5c on 2c, which was never actually used but was created by postal authorities.
See also: Vietnam rare stamps for philatelists and other buyers
There are various overprint varieties that give some Annam and Tonkin stamps a premium value (including, but not limited to, those with sideways, inverted, and/or double overprints). In 1892, stamps of French Indochina were used in Annam and Tonkin and in surrounding areas of Vietnam, Laos, and Cambodia.