Era guide · 1901–1907

Undivided Back era

From 1901, privately printed cards could say “Post Card,” but one rule held: the back belonged to the address alone. No message line, no divider — an undivided back. Senders kept writing on the fronts, and printers began leaving small blank spaces in the image for exactly that purpose.

The era ends precisely: on March 1, 1907, the US Post Office permitted the back to be divided — message on the left, address on the right. An undivided back on a US-published card therefore dates it before March 1907 with unusual confidence for something printed with no date.

The undivided back of a 1907 Raphael Tuck postcard from the Postcard Origins collection, the whole back given over to the address — An undivided back in the flesh: this Raphael Tuck card of Vicksburg gives the entire back to the address, with no dividing line — the layout that places its printing before March 1907. It was mailed in December 1907, early stock used up after the rules had already changed. Scanned from the Postcard Origins collection

One caution for cards with European origins: Britain permitted divided backs in 1902 and France in 1904, so a divided-back card printed abroad can be a few years older than the same layout would suggest for an American card. Check the publisher line and any country imprint before applying US era boundaries.

Compiled and edited by Julien, a postcard dealer and collector in California — every card here is one from the collection.

All eras Dating wizard