A '''postage meter''' is an electro-mechanical device for producing evidence of cancellation and a dated postmark all in one. The meter indicia serves as proof of payment and eliminates the need for adhesive stamps.<ref name="ASME1986">The American Society of Mechanical Engineers, Historical Engineering Landmarks, September 1986</ref> 

The postage meter was introduced in the United States in 1912 by Arthur Pitney, who in 1920 went into business with partner Walter Bowes in order to produce the machines.

Postage meters have evolved from purely mechanical devices to today's Internet-based postage dispensing services.  The evolution of the postage meter is covered in the following sections.

=== History ===

Since the issuance of adhesive stamps in 1847, postal officials have been concerned about security against stamp theft and how to process mail in a timely fashion.<ref name="ASME1986"/>  As early as 1884, a Frenchman, Carle Bushe, obtained a British patent for a device that would print a “stamp” on an envelope and record the amount of postage by means of a counting device, or meter.  Inventors in Germany, Norway, Australia, New Zealand and Great Britain pursued similar idea in the late 1800’s, but nothing came to pass. <ref></ref>

Working independently, a young Chicago inventor, Arthur Hill Pitney, obtained his first mailing system patent in 1902.  Shortly after, he formed the Pitney Postal Machine Company, which became the American Postage Meter Company in 1912  The first machine consisted of a manual crank, chain action, printing die, counter and lockout device.

In 1919, Pitney joined forces with Walter H. Bowes, an entrepreneur who had achieved prominence in postal circles through his company, the Universal Stamping Machine Company, which manufactured post office canceling machines.  In 1920, the two companies merged to create the Pitney-Bowes Postage Meter Company.<ref></ref>

The Model M Postage Meter was authorized on September 1, 2002 and was put into commercial use in Stamford later that year.  (In 1986, the American Society of Mechanical Engineers designated the Model M as an International Historic Mechanical Engineering Landmark).<ref name="ASME1986"/>

==Function==
The postage meter normally consists of a keyboard for entering the postage, three seals, and a stamping mechanism. Years ago, users needed to bring their meter to a postal office in order to add additional postage (sometimes called a “reset” or “refill”). That changed in 1979 when Pitney Bowes invented remote meter resetting, otherwise known as Postage by Phone®.  Today, users can add to their postage balance by prepaid cards, via the web or through a direct connection over the Internet.  The first counter shows the remaining balance. The second counter shows the total postage of the franked consignments. The third one counts the amount of prints and is for statistic purposes only.

If the integrated scales are disabled, the postage has to be entered manually via the keyboard. Otherwise the machine calculates the postage regarding the dimensions and the weight of the consignment. Afterwards the letters are automatically run through an aperture, which is limited to the largest allowed dimensions, and the postage is imprinted. The balance-counter subtracts the imprinted value from the balance, the counter of the total adds the same value, and the printing-counter adds one. If the desired postage is no longer topped up, imprinting is denied. After running through, the consignment arrives at the collect pan orientated "postmark up/front". For thicker consignments there are peelable postage strips, which are manually inserted into the machine via an entry on the side.

== Types of meters ==

=== Mechanical, manual and rotary-print head meters ===
Mechanical meters are letterpress meters that had to be taken to the post office and physically reset by a postal official.  These meters were decertified and taken out of circulation by the USPS in 1999.

Manual Set and Rotary Print Head meters were decertified by the USPS in 2002.  While more advanced, including remote meter resetting capabilities, this early technology was deemed susceptible to tampering.<ref>US General Services Administration, Secure Meter Enhancement and Migration Phases</ref>

thumb|right|Empreinte de machine à affranchir de Belgique de 2005.
Une '''machine à affranchir''' est un outil de bureau qui imprime des marques postales ayant valeur d'affranchissement.

Une empreinte de machine à affranchir (EMA) est une forme de timbre-poste, mais également la date de l'impression et n'est pas oblitéré par l'opérateur postal. Les entreprises utilisent ce type de machine pour un gain de temps dans l'affranchissement et d'expédition du courrier. Leur utilisation est souvent liée à un abonnement avec l'opérateur postal.

''Ces empreintes de machine à affranchir ne doivent pas être confondues avec les timbres de distributeur qui sont une forme de timbre-poste et qui sont parfois imprimés sur les mêmes supports. Les timbres de distributeur, comme les autres timbres-poste, ne portent pas de date du jour d'émission et sont oblitérés pendant l'expédition du pli.''

== Principe ==
L'empreinte imprimée par la machine à affranchir comporte trois types d'éléments. Le premier groupe renvoie aux mentions habituelles d'un timbre-poste : valeur faciale et nom du pays d'émission. 

Le second concerne le statut de timbre préoblitéré : date et lieu de la réalisation. Le courrier doit être remis sous certaines conditions à l'opérateur postal : le jour même de l'oblitération par exemple.

Le troisième groupe d'information concerne l'abonnement liant l'entreprise à l'opérateur postal : numéro de série de la machine et de l'abonnement.