A postal marking is any kind of annotation applied to a
letter by a postal service. The most common types are
postmark
A postmark is a postal marking made on an envelope, parcel, postcard or the like, indicating the place, date and time that the item was delivered into the care of a postal service, or sometimes indicating where and when received or in transit. ...
s and
cancellations; almost every letter will have those. Less common types include forwarding addresses, routing annotations, warnings,
postage due
Postage due is the term used for mail sent with insufficient postage. A postage due stamp is a stamp added to an underpaid piece of mail to indicate the extra postage due.
Background
While the problem of what to do about letters not paying the ...
notices and explanations, such as for damaged or delayed mail and censored or inspected mail. A key part of
postal history
Postal history is the study of postal systems and how they operate and, or, the study of the use of postage stamps and covers and associated postal artifacts illustrating historical episodes in the development of postal systems. The term is att ...
is the identification of postal markings, their purpose, and period of use.
Service marks provide information to the sender, recipient, or another post office. Advice marks notify about forwarding, missending, letters received in bad condition, letters received too late for delivery by a certain time, or the reason for a delay in mail delivery. (For example, a letter may be marked "snowbank" if snow accumulation not cleared by the potential recipient, or for whatever other reason, makes it difficult or impossible for the carrier to deliver the mail.)
Dead letter office
Dead letter mail or undeliverable mail is mail that cannot be delivered to the addressee or returned to the sender. This is usually due to lack of compliance with postal regulations, an incomplete address and return address, or the inability t ...
s would use various markings to keep track of their progress in finding the addressee, such as a notation that the letter had been advertised in the local newspaper. The tracking process for
registered mail
Registered mail is a mail service offered by postal services in many countries which allows the sender proof of mailing via a mailing receipt and, upon request, electronic verification that an article was delivered or that a delivery attempt was ...
may entail multiple marks, notations and
backstamp
In philately a backstamp is a postmark on the back of a letter showing a post office or station through which the item passed in transit. The office of delivery may also backstamp a cover and this type of mark is known as a receiving mark.
Bac ...
s.
Auxiliary marks are applied by an organization other than the postal administration. For instance, 19th century mail delivery often relied on a mix of private ships,