Private cancellations are cancellations of postage stamps, or, in some cases, artistamps, applied by other than a government or other official stamp-issuing entity. Private postmarks are commonly used with private postal meters, but in the United States there is a rule that if the time of posting is significant and there is both a private and regular cancellation, the regular cancellation controls.[1][1] Private postmarks are also not considered in some other cases.[2]
They are also occasionally used to create first day of issues for personalized U.S. postage (officially defined as meter labels and thus not requiring cancellation).[3] Private cancellations are often applied by local posts to their stamps (there are frequently also first day of issues of these).
Another type of private cancellation, in the United States, is the Mailer's Postmark Permit, by which licence-holders can cancel their own mail under certain conditions. They can also, in the U.S., be applied to mail carried outside the post by authority of the private express statutes. An example of this is the Chickensville Location, Michigan private cancellation, applied to mail so carried although Chickensville Location does not have a post office.
Private postmarks have also been used (as backstamps) showing the name, presumably, of the firm from which the mail was posted.[4]
In Britain private cancellations can be seen on Phil Stamp's covers.