Illinois · Central Time
730 Area Code
Area code 730 is in Illinois, serving southern Illinois, including the Metro East near St. Louis and Carbondale. It is in the Central Time zone. It shares its territory with overlay code 618, so 10-digit dialing is required.
Last updated October 1, 2026 · Source: NANPA
Where is the 730 area code?
730 is a Illinois area code covering southern Illinois, including the Metro East near St. Louis and Carbondale. In the wider directory it sits in the Midwest region.
Cities in the 730 area code
- Belleville
- O'Fallon
- Granite City
- Edwardsville
- Collinsville
- Alton
- Carbondale
- Mount Vernon
- Marion
- Centralia
- East St. Louis
- Godfrey
Counties served by 730
St. Clair County, Madison County, Jackson County, Williamson County, Jefferson County, Marion County, Clinton County, Monroe County, Franklin County and Randolph County.
730 overlay codes and dialing
The 730 territory is covered by an overlay of 2 area codes: 618, 730. All of them serve the same geographic area, and the original code is 618. Because more than one code covers the same ground, 10-digit dialing is mandatory — you must dial the area code for every local call. New phone lines may be assigned any of these codes.
History of the 730 area code
730 went into service on July 7, 2023 as an overlay of 618, relieving number exhaustion in the Belleville area. Rather than splitting the region, the overlay lets existing customers keep their numbers while new lines draw from the added code. Learn more in our overlay guide.
Is 730 a scam or spam risk?
730 is a legitimate geographic area code, not a premium or toll line, so a call from it costs you nothing extra. That said, scammers frequently spoof real local area codes to look familiar on caller ID. A genuine 730 number on your screen is no guarantee the caller is in Belleville, IL or trustworthy. See spam & scam-risk area codes for how spoofing works and how to respond.
Other Illinois area codes
Explore more
See every code in Illinois, compare codes across the Midwest region, or view all Central Time codes. You can also browse the 7XX block or the complete numeric list of US area codes.
New to how this all works? Start with how area codes work, then read up on overlays, 10-digit dialing, and spam & scam-risk codes. To check another number, use the area code lookup tool.
Quick answers
730 area code FAQ
Where is the 730 area code?
The 730 area code is in Illinois, covering southern Illinois, including the Metro East near St. Louis and Carbondale, in the Midwest region.
What cities are in the 730 area code?
Cities in the 730 area code include Belleville, O'Fallon, Granite City, Edwardsville, Collinsville, Alton, Carbondale, Mount Vernon, Marion and Centralia.
What time zone is 730 in?
730 is in the Central Time zone.
What is the overlay for the 730 area code?
730 shares its territory with 618. Both codes (618, 730) serve the same area, so 10-digit dialing is required for every call.
When did the 730 area code start?
730 went into service on July 7, 2023 as an overlay of 618.
Do I have to dial 10 digits for 730?
Yes. Because 730 is an overlay area, you must dial the full 10-digit number (area code + 7 digits) for every call.
Is 730 a toll-free or premium code?
No. 730 is a standard geographic area code, so calling it costs the same as any local or long-distance call on your plan. Toll-free calls use 800, 888, 877, 866, 855, 844 or 833.