Package tracking number

A package tracking number is assigned by shipping companies to packages being sent so that their delivery status can be looked up. In the old days you had to call and read the number to an operator to find out the status, but now you can just type it into a web form.

Postal systems that are members of the Universal Postal Union (UPU) have a standard called S10 for tracking numbers; the United States Postal Service uses it. Other shipping companies such as UPS and FedEx have their own systems that don't follow any universal standard; they are various strings of numbers and letters that are unique within a shipping company but not part of any cross-company system.

Some shipping services start out with a private-sector shipping company and end up bringing the package to a post office to be delivered in the regular postal system (e.g., UPS Mail Innovations and FedEx SmartPost); packages in these services will generally have two tracking numbers, one for the independent shipping company and one for the postal system. Looking up the tracking number in the shipping company's site will usually yield tracking information that includes the relayed info from the postal system, or else a link to the postal system's tracking site with the number for that system embedded.

A tracking number may be assigned by the shipping company when a package is brought in or picked up to be sent, or may be pre-printed on a shipping form a shipper obtains from the shipping company and fills out when sending a package, or may be generated by software used by a shipper to label outgoing packages. The shipping label will generally have a bar code with the tracking number so that it may be scanned at various times in the process of transporting and delivering the package.

Tracking sites

 * DHL
 * FedEx
 * UPS
 * USPS

Links

 * Wikipedia: Tracking number
 * Wikipedia: S10