U.S. Machine Cancel Finder -- Years Before 1920
This page is the starting place for identifying
a machine cancellation on mail from the United
States in the general period pre-1920.
Some of the information used here came
from the Machine Cancel Society
and other pointers to particular cancellations
were derived from
the very fine book Postmarks on Postcards
by the late
Richard W. Helbock
I highly recommend Mr. Helbock's book as a
great starting-place for new cover
and card collectors who want to
learn more about postmarks. The book covers only the postcard era (1900-1920) in
the United States. I urge you to
purchase your own copy of the book.
You can purchase it from these sources:
Kindle edition of "Postmarks on Postcards" from Amazon,
copy of "Postmarks on Postcards" from James Lee.
A very good overview of machine cancellations is
available from The Machine
Cancel Society in the form of an award-winning exhibit
on the history of Boston machine cancels, by William
Barlow, Jr. (recently updated) Viewing this exhibit is a great education in
not only the evolution of machines in a major U. S. city,
but also helps the reader to understand that these early
cancels can sometimes be difficult to identify.
My web pages are here for one reason: to help you to
identify the machine cancel on a cover or card from before 1920.
So, let's get started. Keep the cover or card (or a photocopy)
in front of you, and follow the information and links
on this web page.
First, a quick nomenclature lesson:
Note that the "cancellation" or "killer" is the part
that prevents the stamp from being reused. The "postmark"
or "dial" is the part of the impression that tells you where the letter
was mailed and when. Various dial designs were based on
in use by U. S. post offices of the 19th century.
machine cancel inventors approached the problem of
cancelling the stamp, they used a great variety of
designs to ensure that the stamp was obliterated by
ink, even when a cover or card was machine-fed at
If you want, you can jump directly to
the webpage with
a list of machine cancel dials and killers. You
pick your item from the page, based on the
design, and will be sent to a page or pages
that will guide you in the identification.
Alternatively, you may follow the question-and-answer
flow that follows:
Question: Is the date in the postmark:
From 1900 to 1920?
Page Layout Design Made Possible by:
Updated February 25, 2019
Copyright©1996 - 2019 Robert Swanson
Machine Cancel Page
Postal History Page
Machine Cancel Society Page
Return to Swansons Main Page