O Fallon MO ZIP Code
O Fallon city is located in Missouri State, Saint Charles County and has a unique zip code assigned by the US Postal Service Office.
You can search for the O Fallon MO zip code by its streets and block numbers if we have some of the O Fallon streets loaded in our website
O Fallon Area Code is 636 and Time Zone is Central (GMT -06:00).
O Fallon Zip Code - Missouri
The US ZIP Code basic format consists of five decimal numerical digits assigned to the O Fallon City. An extended ZIP+4 code, introduced in the 1980s, includes the five digits of the O Fallon ZIP code, a hyphen, and four more digits that determine a more specific location within a given ZIP code in O Fallon, Missouri.
The O Fallon Zip Code is 63366, 63368.
If you want to send a mail to O Fallon City, you should use the 63366, 63368 Zip Code.
In 1983, the U.S. Postal Service introduced an expanded O Fallon ZIP code system that it called ZIP+4, often called "plus-four codes", "add-on codes", or "add ons". A ZIP+4 code uses the basic 63366, 63368 Zip code plus four additional digits to identify a geographic segment within the five-digit delivery area, such as a O Fallon city block, a group of apartments, an individual high-volume receiver of mail or any other unit that could use an extra identifier to aid in efficient mail sorting and delivery in Missouri.