ZIP codes in St. Louis, Missouri, include 63101, 63102, 63103, 63104 and 63015. The St. Louis ZIP codes start at 63101 and end at 63199. In Worth County, Missouri's least populated county, the ZIP codes are 64486, 64499, 64456 and 64441.Continue Reading
The ZIP codes for the city of Chesterfield are 63017 and 63005. The ZIP code for the city of Allenton is 63001, the first of Missouri's ZIP codes when sorted in numerical order. The last numerical ZIP code in Missouri is 65899, in the city of Springfield in Greene County. All of Missouri's five-digit ZIP codes begin with the number 6. The ZIP codes for Illinois, Kansas and Nebraska also start with 6.
"ZIP" is an acronym for zone improvement plan. ZIP codes allow the United States Postal Service to sort mail for delivery more effectively. The first three numbers of the ZIP code direct the mail to a sectional center facility, which is a regional mailing center. The last two numbers of the ZIP code direct the mail to a specific post office. The ZIP+4 system began in 1983, and it helps direct mail more precisely. However, it is not mandatory to use a ZIP+4 in an address.Learn more about Mail & Shipping