The state of Missouri, USA is currently served by a total of 7 area codes:
These Missouri area codes overlay (cover the same geographic area). The first code listed is the parent code. Overlay area codes are added when no more phone numbers are available in an existing Numbering Plan Area.
| City | County | Area code(s) |
|---|---|---|
| Ballwin | St Louis | 636 |
| Blue Springs | Jackson | 816 |
| Cape Girardeau | Cape Girardeau | 573 |
| Chesterfield | St Louis | 636 |
| Columbia | Boone | 573 |
| Florissant | St Louis | 314/557 |
| Independence | Jackson | 816 |
| Jefferson City | Cole | 573 |
| Joplin | Jasper | 417 |
| Kansas City | Platte | 816 |
| Lee's Summit | Jackson | 816 |
| Liberty | Clay | 816 |
| O'Fallon | St Charles | 636 |
| Oakville | St Louis | 314/557 |
| Springfield | Greene | 417 |
| St Charles | St Charles | 636 |
| St Joseph | Buchanan | 816 |
| St Louis | St Louis | 314/557 |
| St Peters | St Charles | 636 |
| University City | St Louis | 314/557 |
| Wentzville | St Charles | 636 |