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Historical language

Insertion codes (1t, 3t)

A printer’s code from historical newspaper ads, explained with real examples from the archive.


Printers’ codes at the end of a newspaper ad, such as 1t or 3t, telling staff, not readers, how many times to run it.

TypeHistorical language
CategoryPeriod vocabulary
Earliest example in the archiveOctober 27, 1855, Shasta Courier (California)
Most common1850s to the 1920s

History

Printers marked ads for their own staff long before personal ads were common: colonial papers printed notes such as the issue numbers of an ad’s first and last appearance, so the compositor knew whether to set it again. In the archive, the codes read as a start date and a count. An 1855 notice in the Shasta Courier ends o20-3t, first run October 20, three times, and an 1872 ad ends dec 12-1t, December 12, one time. In the Arizona Republican of 1917 to 1922, 1t meant one time, and in El Tucsonense in 1919, 3t meant three. Other Arizona Republican ads end in letters, such as bg, bn, or dn, internal codes we haven’t been able to decode.

Sources: The Adverts 250 Project, on printers’ notations.

In the archive

Today

Online posts don’t need them: an ad stays up until it expires or its writer takes it down.

Related terms

Box, care of the officePersonal column

How to cite this entry

“Insertion codes (1t, 3t).” The Personals Dictionary, AseeksB, 2026, https://www.aseeksb.com/dictionary/insertion-codes.html.
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