U.S. Postal Service Official Explains WR ZIP Code

Manager, Post Office Operations
U.S. Postal Service

It’s important to provide some clarification regarding Ms. Camille Morrison’s July 12 letter to the Los Alamos Post regarding the new ZIP Code, 87547, which was assigned to White Rock on July 1.

The ZIP (Zone Improvement Plan) Code system was created by the U.S. Postal Service in 1963 for the sole purpose of providing cost-effective and efficient delivery of the mail. The USPS assigns a default city name when it creates a ZIP Code. White Rock has been assigned to the new ZIP Code 87547.

Large mailers such as banks and credit card companies, etc., use the ZIP Code and its default name to send their mail, and will use White Rock as the default city name when they update the address matching software they use during the next several months.

Before the new 87547 ZIP Code was created on July 1, the single ZIP Code 87544 was used in both Los Alamos and White Rock, with Los Alamos assigned as the default city name. With this ZIP Code addition, Postal customers living in White Rock have the option of using either White Rock or Los Alamos on their postal correspondence. All USPS infrastructure and automated sorting
equipment will recognize either city name as valid. However, White Rock will be the default city name that online retailers or shipping companies other than the Postal Service will use.

In short, if you send a letter to someone, you may use either White Rock, NM 87547 or Los Alamos, NM 87547. However; when your ZIP Code is updated by any bank or large retailer, etc., they will now see only White Rock as the city name for 87547. In either case, our customers in the new ZIP Code area can rest assured that the U.S. Postal Service will deliver their mail safely and