Missouri has 9 active area codes serving its major cities and rural communities across the Central Time Zone. The entire state follows Central Standard Time (CST), which is UTC-6, or Central Daylight Time (CDT) at UTC-5 during daylight saving months. Whether you need to identify an unknown caller, plan business communications across Missouri, or schedule calls with confidence, this guide provides complete and current information about every Missouri area code.
Quick Summary
Missouri’s 9 area codes include three overlay pairs (314/557, 573/235, and 816/975) plus three standalone codes (417, 636, and 660). The most recently added was 235 in March 2024 as an overlay to 573. All codes operate in the Central Time Zone, and most urban areas now require 10-digit dialing for all local calls.
The 816 area code serves the largest population with approximately 1.4 million residents in the Kansas City metropolitan region.
Quick Reference Table: Missouri Area Codes
| Area Code | Primary Cities/Regions | Time Zone | Type | Year Introduced |
|---|---|---|---|---|
| 235 | Columbia, Jefferson City, Cape Girardeau | Central (CST/CDT) | Overlay | 2024 |
| 314 | St. Louis (city core), University City | Central (CST/CDT) | Original | 1947 |
| 417 | Springfield, Joplin, Branson | Central (CST/CDT) | Split | 1950 |
| 557 | St. Louis (city core), University City | Central (CST/CDT) | Overlay | 2022 |
| 573 | Columbia, Jefferson City, Cape Girardeau | Central (CST/CDT) | Split | 1996 |
| 636 | St. Charles, O’Fallon, Chesterfield | Central (CST/CDT) | Split | 1999 |
| 660 | Sedalia, Kirksville, Maryville | Central (CST/CDT) | Split | 1997 |
| 816 | Kansas City, Independence, St. Joseph | Central (CST/CDT) | Original | 1947 |
| 975 | Kansas City, Independence, St. Joseph | Central (CST/CDT) | Overlay | 2023 |
Detailed Area Code Descriptions
Area Code 314: St. Louis Core
Area code 314 serves the city of St. Louis and most inner-ring suburbs in neighboring St. Louis County. This includes communities like University City, Clayton, Webster Groves, and portions of the immediate metropolitan area.
Historical Significance
Area code 314 was one of Missouri’s two original area codes established in 1947 when the North American Numbering Plan was first implemented. For over 40 years, it served all of eastern Missouri, including the entire St. Louis metropolitan region.
Evolution and Changes
The code underwent its first split in 1996 when area code 573 was created to serve areas outside the immediate St. Louis region. A second split occurred in 1999 when 636 was introduced for St. Louis County suburbs. Most recently, 314 received its first overlay in August 2022 with the addition of area code 557.
Current Coverage
Today, 314 serves approximately 2.8 million people in the St. Louis metropolitan core. Ten-digit dialing has been mandatory since October 2021, initially implemented for the 988 crisis hotline and continuing with the 557 overlay. The region includes major institutions like Washington University, Saint Louis University, and numerous Fortune 500 company headquarters.
Area Code 557: St. Louis Overlay
Area code 557 was activated on August 12, 2022, as Missouri’s first overlay code. An overlay adds a new area code to the same geographic region without splitting the territory or requiring existing customers to change their numbers.
Coverage and Cities
The 557 overlay covers exactly the same geographic area as 314, serving the city of St. Louis and inner-ring suburbs. All locations that can receive a 314 number can also receive a 557 number.
Why the Overlay Was Needed
The overlay was necessary because 314 was projected to exhaust its available telephone numbers by late 2022. The rapid growth of mobile phones, internet-connected devices, and business lines created demand that exceeded the original numbering capacity.
Current Usage
New phone numbers in the St. Louis core area may be assigned either 314 or 557, depending on availability. Existing 314 customers kept their numbers unchanged. The overlay has extended the region’s number supply until approximately 2063 according to current projections.
Area Code 636: St. Louis County Suburbs
Area code 636 covers the outer St. Louis County suburbs and surrounding areas, including St. Charles County, Jefferson County, Franklin County, and portions of Warren County. This spans roughly 30 miles west and southwest of downtown St. Louis.
Major Cities and Communities
The code serves major suburban cities, including St. Charles, O’Fallon, St. Peters, Wentzville, Chesterfield (western portions), Lake St. Louis, Troy, Washington, Union, and De Soto. These communities experienced rapid growth in the 1980s and 1990s.
History and Implementation
Introduced on May 22, 1999, area code 636 was created through a split from 314 to accommodate the exploding telecommunications needs of the St. Louis suburbs. The suburban population boom, combined with the rise of cell phones and fax machines, necessitated additional number capacity.
Economic and Cultural Significance
The 636 region represents Missouri’s fastest-growing suburban corridor with strong retail, manufacturing, and logistics sectors. The area includes major employers like MasterCard’s global headquarters in O’Fallon and numerous distribution centers along Interstate 70.
Area Code 573: Central and Eastern Missouri
Area code 573 was created on January 7, 1996, through a split from the original 314 code. It was designed to serve the vast areas of eastern Missouri outside the immediate St. Louis metropolitan region.
Geographic Coverage
The 573 region encompasses approximately 50 counties across central, northeastern, and southeastern Missouri. This includes the Lake of the Ozarks region to the west and the entire Missouri Bootheel area bordering Arkansas and Tennessee.
Major Cities and Institutions
Key cities include Columbia (home to the University of Missouri), Jefferson City (the state capital), Cape Girardeau, Rolla (Missouri University of Science and Technology), Hannibal, Poplar Bluff, Farmington, and Sikeston. Fort Leonard Wood, a major U.S. Army installation, also falls within this area code.
Evolution and Recent Changes
In March 2024, 573 received an overlay code (235) after projected number exhaustion by 2025. The mandatory 10-digit dialing began on February 24, 2024, with new 235 numbers assigned starting March 24, 2024. The region serves approximately 1.5 million residents across diverse landscapes from agricultural heartlands to educational and government hubs.
Area Code 235: Central Missouri Overlay
✨ NEW: Activated March 24, 2024
Area code 235 is Missouri’s newest code, activated on March 24, 2024. The Missouri Public Service Commission approved this overlay to address the projected exhaustion of 573 numbers. A permissive dialing period ran from August 26, 2023, to February 23, 2024, allowing residents to adjust to the new 10-digit dialing requirement.
Coverage Area
The 235 overlay covers exactly the same geographic footprint as 573, serving approximately 50 counties in central, northeastern, and southeastern Missouri. This includes major cities like Columbia, Jefferson City, Cape Girardeau, and Rolla.
What This Means for Residents
Existing 573 customers retained their phone numbers with no changes required. New lines and services requested after March 24, 2024, may receive either a 573 or 235 number. All local calls now require 10 digits (area code plus seven-digit number), but call rates, coverage areas, and emergency services (911, 988) remain unchanged.
Area Code 816: Kansas City and Northwest Missouri
Area code 816 was Missouri’s second original area code, established in 1947 to serve northwestern Missouri. Initially, it covered a much larger territory before undergoing splits to accommodate population growth.
Geographic Coverage and Population
Today, 816 serves the Kansas City metropolitan area and surrounding counties, including Jackson, Clay, Platte, Cass, and parts of Ray and Bates counties. The region encompasses approximately 1.4 million residents, making it Missouri’s most populous area code by population.
Major Cities and Communities
Key cities include Kansas City, Independence, Lee’s Summit, Blue Springs, St. Joseph, Gladstone, Grandview, Raytown, Liberty, Belton, and numerous smaller communities. The area includes major economic drivers like Kansas City’s logistics hub, financial services sector, and healthcare institutions.
Evolution and Current Status
Area code 816 underwent its first split in 1997 when 660 was created for northern and west-central Missouri. The code received an overlay (975) in October 2023 due to projected number exhaustion. The region operates entirely in the Central Time Zone with mandatory 10-digit dialing since October 2021.
Area Code 975: Kansas City Overlay
Area code 975 was activated on October 13, 2023, as an overlay for the 816 region. This was Missouri’s second overlay code, following the 557 overlay in the St. Louis area.
Coverage and Cities
The 975 overlay serves exactly the same geographic area as 816, covering the Kansas City metropolitan region, St. Joseph, and surrounding northwestern Missouri communities. Every location that can receive an 816 number can also receive a 975 number.
Why the Overlay Was Needed
The Kansas City area’s sustained population growth, technology sector expansion, and logistics industry boom created exceptional demand for new phone numbers. The 816 code was projected to be exhausted by the second quarter of 2024, necessitating immediate action to maintain an adequate number supply.
Current Usage
New telephone lines and services may be assigned either 816 or 975 numbers. All existing 816 numbers remain unchanged. Ten-digit dialing was already mandatory before the overlay, simplifying the transition. Current projections indicate the combined 816/975 number supply will last until approximately 2071.
Area Code 660: Northern and West-Central Missouri
Area code 660 covers approximately 42 counties across northern and west-central Missouri. This includes portions of the state north of the Missouri River and extends westward toward the Kansas border.
Major Cities and Communities
The code serves Sedalia, Kirksville (home to Truman State University), Maryville (Northwest Missouri State University), Marshall, Moberly, Warrensburg (University of Central Missouri), and numerous smaller towns. The region is predominantly rural with agricultural and educational economies.
History and Implementation
Created on October 12, 1997, area code 660 was carved out of the original 816 territory. The split was necessary to accommodate growing telecommunications needs in both urban Kansas City (which retained 816) and the rural areas requiring additional capacity.
Regional Characteristics
The 660 region serves approximately 700,000 residents across largely rural and small-town landscapes. Major economic activities include agriculture, higher education, manufacturing, and tourism around scenic areas like the Lake of the Ozarks’ northern sections.
Area Code 417: Southwest Missouri
Area code 417 encompasses the southwestern quadrant of Missouri, covering approximately 30 counties. This region includes the scenic Ozarks terrain with rugged hills, valleys, and numerous lakes.
Major Cities and Communities
Key cities include Springfield (Missouri’s third-largest city), Joplin, Branson (a major tourism destination), Carthage, Lebanon, Neosho, Nixa, Ozark, West Plains, and Carl Junction. The region blends urban centers with extensive rural areas.
Historical Background
Introduced in 1950, area code 417 was Missouri’s third area code, created through adjustments to the original 314 and 816 boundaries. It has remained geographically stable for over 70 years, a testament to its efficient original sizing.
Economic and Cultural Importance
The 417 region is known for Branson’s entertainment industry, Springfield’s healthcare and education sectors (Missouri State University, Drury University), and Joplin’s position as a regional commercial hub. Manufacturing, agriculture, and tourism drive the economy. Current projections suggest 417 won’t require an overlay or split until approximately 2031.
Understanding Time Zones in Missouri
Missouri operates entirely within the Central Time Zone. Every county, city, and community in the state follows the same time, eliminating confusion when calling between Missouri locations. This uniform time zone makes Missouri unique among its neighboring states, several of which span multiple zones.
UTC Offset and DST
During standard time (November through March), Missouri observes Central Standard Time (CST) at UTC-6, meaning it is six hours behind Coordinated Universal Time. During daylight saving time (March through November), the state shifts to Central Daylight Time (CDT) at UTC-5.
Daylight saving time begins on the second Sunday in March at 2:00 AM, when clocks spring forward to 3:00 AM. It ends on the first Sunday in November at 2:00 AM, when clocks fall back to 1:00 AM. Missouri consistently observes these changes statewide with no exceptions.
Scheduling Across Time Zones
When scheduling calls or meetings with people in Missouri from other time zones, remember that Missouri is one hour behind Eastern Time, one hour ahead of Mountain Time, and two hours ahead of Pacific Time. All neighboring states (Iowa, Kansas, Nebraska, Oklahoma, Illinois, Arkansas, Kentucky, and Tennessee) also use Central Time, making cross-border communications straightforward.
For international calls, Missouri is typically 6-7 hours behind most of Western Europe, 13-14 hours behind East Asia, and 15-17 hours behind Australia, depending on respective daylight saving observances.
Missouri Cities and Their Area Codes
Largest Cities by Population
- Kansas City – 816, 975 – Population: ~508,000
- St. Louis – 314, 557 – Population: ~286,000
- Springfield – 417 – Population: ~169,000
- Columbia – 573, 235 – Population: ~126,000
- Independence – 816, 975 – Population: ~123,000
- Lee’s Summit – 816, 975 – Population: ~101,000
- O’Fallon – 636 – Population: ~91,000
- St. Joseph – 816, 975 – Population: ~72,000
- St. Charles – 636 – Population: ~71,000
- St. Peters – 636 – Population: ~58,000
- Blue Springs – 816, 975 – Population: ~58,000
- Florissant – 314, 557 – Population: ~52,000
- Joplin – 417 – Population: ~51,000
- Chesterfield – 636, 314 – Population: ~49,000
- Jefferson City – 573, 235 – Population: ~43,000 (State Capital)
How to Use Area Codes in Missouri
Local Calling Requirements
Most of Missouri now requires 10-digit dialing for all local calls. This means you must dial the area code plus the seven-digit phone number, even when calling someone in the same area code. This requirement applies to all regions with overlay codes: 314/557, 573/235, and 816/975.
In areas without overlays (417, 636, and 660), 10-digit dialing is also standard practice for consistency, though some carriers may still accept 7-digit local dialing. When in doubt, always use 10 digits for local calls within Missouri.
Calling from Outside Missouri
To call Missouri from elsewhere in the United States or Canada, dial 1 plus the area code plus the seven-digit number. For example, to call a Kansas City number, dial 1-816-XXX-XXXX or 1-975-XXX-XXXX.
International Calling to Missouri
To call Missouri from outside North America, dial your country’s international access code (often 00 or 011), then 1 (the country code for the United States), then the area code, then the seven-digit number. For example, from the UK: 00-1-314-XXX-XXXX.
Mobile and Landline Considerations
Area codes in Missouri apply equally to mobile phones and landlines. Unlike some countries where mobile numbers have distinct prefixes, U.S. phone numbers don’t indicate whether they’re mobile or landline based on the area code. An 816 number could be a Kansas City cell phone, business line, or home phone.
Frequently Asked Questions
What is the newest Missouri area code?
Area code 235 is Missouri’s newest code, activated on March 24, 2024. It serves as an overlay for area code 573 in central and eastern Missouri, covering cities like Columbia, Jefferson City, and Cape Girardeau. The overlay was necessary because the 573 area code was projected to run out of available numbers by 2025. Existing 573 customers retained their numbers, while new lines may receive either 573 or 235 numbers.
Why does St. Louis have two area codes?
St. Louis has two area codes (314 and 557) because of an overlay implemented in August 2022. An overlay adds a new area code to the same geographic region when the existing code approaches number exhaustion. Rather than splitting the area or forcing customers to change numbers, both codes now serve the same locations.
New phone lines receive whichever code has available numbers, while all existing customers keep their original 314 numbers.
Do I need to dial 10 digits for local calls in Missouri?
Yes, 10-digit dialing is required for local calls in most of Missouri. All areas with overlay codes (314/557 in St. Louis, 573/235 in central Missouri, and 816/975 in Kansas City) mandate 10-digit dialing. This means you must dial the area code plus the seven-digit number even when calling someone in the same area code. Areas without overlays (417, 636, 660) have also largely adopted 10-digit dialing for consistency.
When was the 816 area code created?
Area code 816 was created in 1947 as one of Missouri’s two original area codes when the North American Numbering Plan was first established. It originally covered all of northwestern Missouri, including Kansas City and surrounding regions. The territory has since been reduced through splits, with area code 660 carved out in 1997 and overlay code 975 added in 2023, but 816 remains one of Missouri’s historic original codes.
What parts of Missouri use the 417 area code?
Area code 417 serves southwestern Missouri, covering approximately 30 counties. Major cities include Springfield (the region’s largest city), Joplin, Branson, Carthage, Lebanon, and Neosho. The region encompasses the scenic Ozarks area with its tourism industry, particularly in Branson, as well as Springfield’s healthcare and education sectors. Area code 417 has served this region since 1950 and currently has no overlays.
How many time zones does Missouri have?
Missouri has only one time zone. The entire state observes Central Time, operating at UTC-6 during standard time and UTC-5 during daylight saving time. This makes Missouri one of the few states that doesn’t have to worry about internal time zone differences. All neighboring states (Iowa, Kansas, Nebraska, Oklahoma, Illinois, Arkansas, Kentucky, and Tennessee) also use Central Time, simplifying cross-border communications.
Will Missouri get more area codes in the future?
Yes, Missouri will likely add more area codes as number demand continues. Area code 417 (Springfield region) is projected to need an overlay around 2031. The 314/557, 573/235, and 816/975 overlay regions have extended number supplies until 2063, 2061, and 2071, respectively, but additional overlays may be needed sooner depending on population growth and device proliferation.
The Missouri Public Service Commission monitors number usage and approves new codes in coordination with NANPA.
Additional Resources
For official information about Missouri area codes and telecommunications regulations, visit the Missouri Public Service Commission website. For real-time updates on area code assignments and changes, consult the North American Numbering Plan Administration (NANPA) at nationalnanpa.com.
To look up specific area codes for Missouri cities or verify current time zones, use our search tools above. For questions about upcoming area code changes or overlay implementations, contact the Missouri Public Service Commission directly.