In a postal system, a delivery point (sometimes DP) is a single mailbox or other place at which

mail The mail or post is a system for physically transporting postcards, letters, and parcels. A postal service can be private or public, though many governments place restrictions on private systems. Since the mid-19th century, national postal sys ...

is delivered. It differs from a street address, in that each address may have several delivery points, such as an apartment, office department, or other room. Such buildings (primarily residential) are often called multiple-dwelling units (MDUs) by the

USPS The United States Postal Service (USPS), also known as the Post Office, U.S. Mail, or Postal Service, is an independent agency of the executive branch of the United States federal government responsible for providing postal service in the ...

United States Postal Service usage

In the US Postal System, a delivery point is a specific set of digits between 00 and 99 assigned to every address. When combined with the ZIP + 4 code, the delivery point provides a unique identifier for every deliverable address served by the USPS. The delivery point digits are almost never printed on mail in

human-readable A human-readable medium or human-readable format is any encoding of data or information that can be naturally read by humans. In computing, ''human-readable'' data is often encoded as ASCII or Unicode text, rather than as binary data. In most c ...

form; instead they are encoded in the POSTNET delivery point barcode (DPBC) or as part of the newer

Intelligent Mail Barcode The Intelligent Mail Barcode (IMb) is a 65-bar barcode for use on mail in the United States. The term "Intelligent Mail" refers to services offered by the United States Postal Service for domestic mail delivery. The IM barcode is intended to provi ...

(IMb). The DPBC makes automated mail sorting possible, including ordering the mail according to how the carrier delivers it (walk sequence). The two-digit delivery point number is combined with an additional

check digit A check digit is a form of redundancy check used for error detection on identification numbers, such as bank account numbers, which are used in an application where they will at least sometimes be input manually. It is analogous to a binary parity ...

in the DPBC. This digit is used by barcode sorters (BCS) to check if the ZIP, ZIP+4, or delivery point ZIP codes contain an error. In a database, storing the ZIP+4 code in a 10 character field (with the hyphen) allows easy output in the address block, and storing the check digit in a 3-digit field (instead of calculating it) allows automatic checking of the validity of the ZIP+4 and delivery point fields in case one had been changed independently. In order to receive the appropriate barcode discount, the delivery point digits and the +4 extension must be verified using an up-to-date,

CASS Cass may refer to: People and fictional characters * Cass (surname), a list of people * Cass (given name), a list of people and fictional characters * Big Cass, ring name of wrestler William Morrissey * Cass, in British band Skunk Anansie * Ca ...

or Delivery Point Validation (DPV) certified program. Since each city block or section of a rural route has a different +4 extension, and address numbers generally increase by 100 per block, the delivery point is typically the last two digits of the address. In the early days of DPBC, it was acceptable to determine the delivery point in this fashion, but since suite and other secondary designations are assigned unique delivery points which cannot be determined without the

/DPV database, this is no longer possible. The delivery point is usually redundant for post office boxes, since they are typically assigned their own ZIP+4 code, but must nonetheless be assigned a complete DPBC for full postal discounts. The full rules for identifying the delivery point for a given address are specified in the USPS CASS Technical Guide.

United Kingdom

In the United Kingdom the delivery point index is known as the

Postcode Address File The Postcode Address File (PAF) is a database that contains all known "delivery points" and postcodes in the United Kingdom. The PAF is a collection of over 29 million Royal Mail postal addresses and 1.8 million postcodes. It is available i ...

(PAF). It is owned and made available by Royal Mail.

New Zealand Post

New Zealand Post NZ Post ( mi, Tukurau Aotearoa), shortened from New Zealand Post, is a state-owned enterprise responsible for providing postal service in New Zealand. The New Zealand Post Office, a government agency, provided postal, banking, and telecommuni ...

maintains an index of delivery points known as the National Postal Address Database (NPAD).

Australia Post

In Australia the PAF is maintained by Australia Post.

References

{{reflist Postal systems