How A Letter Travels

Collection

After a customer has deposited a letter destined for a distant address in a collection box, a postal carrier removes all of the mail from the box and takes it to the Post Office where he or she works. That letter and mail collected by other carriers of that Post Office are placed on a truck and taken to a mail processing plant.

 

Culling and Postmarking

Postal workers send the letter through a machine that rapidly separates mail by shape, separating letters from large envelopes and packages (the culling operation). The machine orients letters so that all addresses face the same way and are right side up. It then applies a postmark with the date and place where the letter was sorted and cancellation lines so the stamp cannot be reused, in order to protect postal revenue.

 

Scanning and Lifting Images

Every letter gets identified by a code consisting of a series of florescent bars imprinted on the back. The address on the front of each letter is scanned by an optical character reader. Images of letters that could not be successfully read are transmitted to a remote encoding center for further processing. All letters are placed in trays and moved to the next piece of automated equipment for barcode application.

 

Applying a Barcode and Sorting

Linked with the identification code, a barcode is sprayed on the front of the letter. Representing the specific delivery address, the barcode consists of tall and short bars used for all further sorting. The barcode sends a letter into a bin on the machine for a particular range of ZIP Codes; these identify the next processing plant.

 

Transportation to Processing Plant

The letter is placed in a tray with other mail for the ZIP Code range it falls into, and this tray is taken to the airport to fly across the country. After the plane lands at its destination, postal workers take the tray containing the letter to the mail processing plant that serves the Post Office, station, or branch that will deliver the letter.

 

Sorting into Delivery Order

At the plant, the letters in the tray are fed through a barcode sorter, which separates letters for a specific ZIP Code from other letters in that ZIP Code range. After this, the letter will receive its final sortation. A delivery barcode sorter sorts the letter to the particular carrier who will deliver it. The delivery barcode sorter also arranges that carrier’s letters into the order of delivery.

 

Transportation to Delivery Post Office

Next, all the mail for this carrier is taken by truck to the Post Office, station, or branch in which the carrier works. The carrier loads trays of mail, including the letter, into a motor vehicle.

 

Delivery to Addressee

The carrier drives to the street where the letter is to be delivered, safely parks, then loads his or her satchel with the mail to be carried to each house or business. Within minutes of leaving the truck, the carrier delivers the letter to the addressee.