Rock Falls IL ZIP Code
Rock Falls city is located in Illinois State, Whiteside County and has a unique zip code assigned by the US Postal Service Office.
You can search for the Rock Falls IL zip code by its streets and block numbers if we have some of the Rock Falls streets loaded in our website
Rock Falls Area Code is 815 and Time Zone is Central (GMT -06:00).
Rock Falls Zip Code - Illinois
The US ZIP Code basic format consists of five decimal numerical digits assigned to the Rock Falls City. An extended ZIP+4 code, introduced in the 1980s, includes the five digits of the Rock Falls ZIP code, a hyphen, and four more digits that determine a more specific location within a given ZIP code in Rock Falls, Illinois.
The Rock Falls Zip Code is 61071.
If you want to send a mail to Rock Falls City, you should use the 61071 Zip Code.
In 1983, the U.S. Postal Service introduced an expanded Rock Falls 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 61071 Zip code plus four additional digits to identify a geographic segment within the five-digit delivery area, such as a Rock Falls 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 Illinois.