Tennessee has 8 area codes serving its major cities and communities across two time zones. Most of the state follows Central Time, while eastern counties including Knoxville and Chattanooga use Eastern Time. Whether you need to identify an unknown caller, plan business communications, or schedule calls across regions, this guide provides complete and current information about every Tennessee area code, including the newly activated 729 code.
Key Takeaways:
- Tennessee currently uses 8 active area codes: 423, 615, 629, 731, 729, 865, 901, and 931
- The state spans two time zones (Central and Eastern), with about 65% of counties in Central Time
- 729 is the newest area code, activated in September 2025 as an overlay to 423
- 10-digit dialing is now mandatory statewide for all local calls
- Nashville area (615/629) is the most populated region with approximately 1.6 million residents
Tennessee Area Codes
| Area Code | Primary Cities/Regions | Time Zone | Type | Year Introduced |
|---|---|---|---|---|
| 423 | Chattanooga, Johnson City, Kingsport | Eastern (EST/EDT) | Original | 1995 |
| 615 | Nashville, Murfreesboro, Franklin | Central (CST/CDT) | Original | 1954 |
| 629 | Nashville, Murfreesboro, Franklin | Central (CST/CDT) | Overlay | 2015 |
| 729 | Chattanooga, Johnson City, Kingsport | Eastern (EST/EDT) | Overlay | 2025 |
| 731 | Jackson, Dyersburg, Martin | Central (CST/CDT) | Split | 2001 |
| 865 | Knoxville, Oak Ridge, Maryville | Eastern (EST/EDT) | Split | 1999 |
| 901 | Memphis, Germantown, Collierville | Central (CST/CDT) | Original | 1947 |
| 931 | Clarksville, Cookeville, Columbia | Central (CST/CDT) | Split | 1997 |
Area Code 423: East Tennessee
Created in September 1995 from the original 615 code, area code 423 serves eastern Tennessee including Chattanooga, Johnson City, and Kingsport across 24 counties. The region covers approximately 7,300 square miles in Eastern Time. Due to number exhaustion, the 729 overlay was activated in September 2025, requiring mandatory 10-digit dialing for all local calls.
Area Code 615: Middle Tennessee (Nashville Metro)
Introduced January 1, 1954, area code 615 serves Nashville and 12 surrounding counties including Murfreesboro, Franklin, and Brentwood in Central Time. Originally covering much of Tennessee, it now focuses on the state capital region with approximately 1.6 million residents. The 629 overlay was added in 2015 due to continued growth and number demand.
Area Code 629: Middle Tennessee (Nashville Metro) Overlay
Activated March 28, 2015, area code 629 overlays the 615 region, serving identical geographic territory including Nashville, Murfreesboro, and Franklin. Tennessee’s first overlay code was implemented to provide additional phone numbers without disrupting existing 615 customers. All residents must use 10-digit dialing, with new numbers assigned from either 615 or 629 based on availability.
Area Code 729: East Tennessee (New 423 Overlay)
✨ NEW: Activated September 2025
Area code 729 overlays 423, serving Chattanooga, the Tri-Cities, and surrounding areas. Approved in May 2024 and implemented September 2025, this newest Tennessee code provides additional capacity for eastern regions. Existing 423 numbers remain unchanged while new lines receive 729 assignments. Mandatory 10-digit dialing applies throughout the coverage area.
Area Code 731: West Tennessee
Created February 12, 2001, from the 901 split, area code 731 serves 21 counties in western Tennessee excluding Memphis. Major cities include Jackson, Union City, Martin, and Dyersburg in Central Time. The region spans approximately 7,500 square miles with strong agricultural heritage and manufacturing presence, serving rural communities and growing cities alike.
Area Code 865: Knoxville Metro
Activated November 1, 1999, area code 865 serves Knoxville and nine surrounding counties in Eastern Time. Major cities include Oak Ridge, Maryville, and Sevierville. Notably, 865 spells “VOL” on phone keypads, intentionally chosen to honor University of Tennessee athletics. The region includes gateway communities to Great Smoky Mountains National Park.
Area Code 901: Memphis Metro
Tennessee’s original area code from 1947, 901 initially covered the entire state. Now serving only the Memphis metropolitan area including Germantown, Collierville, and Bartlett in Central Time. The region encompasses Shelby, Fayette, and Tipton counties with approximately 1.3 million residents. Memphis serves as a major logistics hub and FedEx headquarters.
Area Code 931: South-Central Tennessee
Created September 15, 1997, from the 615 split, area code 931 serves 29 counties surrounding Nashville. Major cities include Clarksville, Cookeville, and Columbia in Central Time. Covering approximately 10,500 square miles, it’s one of Tennessee’s largest area codes geographically. The region features diverse economy including Fort Campbell military base and automotive manufacturing.
Understanding Time Zones in Tennessee
Tennessee is divided between two time zones, with the majority of the state observing Central Time. Approximately 65 of Tennessee’s 95 counties, representing about 73% of the state’s geographic area, fall within the Central Time Zone. The remaining 30 counties in the eastern part of the state observe Eastern Time.
UTC Offset and DST
Central Time zones operate at UTC-6 during standard time (CST) and UTC-5 during daylight saving time (CDT). Eastern Time zones operate at UTC-5 during standard time (EST) and UTC-4 during daylight saving time (EDT). All Tennessee counties observe daylight saving time, which begins the second Sunday in March and ends the first Sunday in November.
The Time Zone Boundary
The boundary between Central and Eastern time zones follows the eastern borders of six counties: Pickett, Fentress, Cumberland, Bledsoe, Sequatchie, and Marion. This line roughly corresponds to the edge of the Cumberland Plateau, a natural geographic feature that historically separated population centers.
Practical Tips for Scheduling
When scheduling calls or meetings with Tennessee contacts, remember that Knoxville, Chattanooga, and other eastern cities are one hour ahead of Nashville, Memphis, and Clarksville. For example, when it’s 2:00 PM in Nashville (Central Time), it’s 3:00 PM in Knoxville (Eastern Time). Always confirm time zones when arranging appointments across the state.
Tennessee Cities and Their Area Codes
- Memphis – 901 | Population: ~633,000 | Tennessee’s second-largest city and logistics capital
- Nashville – 615/629 | Population: ~689,000 | State capital and country music center
- Knoxville – 865 | Population: ~190,000 | Home to University of Tennessee
- Chattanooga – 423/729 | Population: ~181,000 | Tech hub and gateway to mountains
- Clarksville – 931 | Population: ~166,000 | Military community near Fort Campbell
- Murfreesboro – 615/629 | Population: ~152,000 | Fastest-growing Tennessee city
- Franklin – 615/629 | Population: ~83,000 | Historic city in Nashville suburbs
- Jackson – 731 | Population: ~68,000 | Regional hub for West Tennessee
- Johnson City – 423/729 | Population: ~71,000 | Part of Tri-Cities region
- Bartlett – 901 | Population: ~59,000 | Memphis suburb
- Hendersonville – 615/629 | Population: ~61,000 | Nashville suburb on Old Hickory Lake
- Kingsport – 423/729 | Population: ~55,000 | Tri-Cities manufacturing center
- Collierville – 901 | Population: ~51,000 | Affluent Memphis suburb
- Cleveland – 423/729 | Population: ~47,000 | Between Chattanooga and Knoxville
- Smyrna – 615/629 | Population: ~53,000 | Home to Nissan assembly plant
How to Use Area Codes in Tennessee
Local Calling Requirements
All areas in Tennessee now require 10-digit dialing for local calls. You must dial the area code plus the seven-digit phone number, even when calling someone in the same area code. This change was implemented gradually across the state, with the 865 region converting to mandatory 10-digit dialing in 2021 and the 423/729 region converting in February 2025.
Calling from Outside the State
When calling Tennessee from elsewhere in the United States, dial 1 + area code + seven-digit number. For example, to call a Nashville number, dial 1-615-555-1234. Long distance charges may apply depending on your calling plan, though most modern mobile and VoIP plans include nationwide calling.
International Dialing Format
To call Tennessee from outside the United States, dial your country’s international access code, then 1 (the country code for the United States), followed by the area code and seven-digit number. For example, from the UK, dial 00-1-615-555-1234.
Mobile and Landline Considerations
Cell phone numbers maintain their original area code even if you move to a different region. Many Tennesseans carry area codes from other parts of the state or country. When you see an unfamiliar area code calling your Tennessee number, it could be a local resident with a different area code or someone calling from elsewhere. Business landlines typically use the local area code for credibility and recognition.
Frequently Asked Questions
What is the oldest area code in Tennessee?
Area code 901 is Tennessee’s oldest, established in 1947 as part of the original North American Numbering Plan. It initially covered the entire state before being reduced to serve only western Tennessee in 1954, and finally just the Memphis metropolitan area in 2001.
Why does Tennessee have two time zones?
Tennessee spans two time zones due to its geographic width and the way federal time zone boundaries were established. The eastern third of the state, including Knoxville and Chattanooga, observes Eastern Time, while the western and middle portions observe Central Time. The boundary roughly follows the Cumberland Plateau, a natural geographic feature that historically separated population and economic centers.
What cities use area code 615?
Area code 615 (along with its overlay 629) serves Nashville and surrounding cities including Murfreesboro, Franklin, Brentwood, Gallatin, Hendersonville, Lebanon, Smyrna, and Mount Juliet. The area covers Davidson County and 12 neighboring counties in Middle Tennessee.
When was the 729 area code activated in Tennessee?
Area code 729 was officially activated on September 5, 2025, as an overlay to the existing 423 area code. The Tennessee Public Utility Commission approved it in May 2024, with implementation occurring in phases. Mandatory 10-digit dialing began February 5, 2025, and new phone numbers started receiving 729 assignments in September 2025.
Additional Resources
For the most current information about Tennessee area codes and any upcoming changes, consult these official sources:
- North American Numbering Plan Administration (NANPA) – Official area code database and announcements
- Tennessee Public Utility Commission – State regulatory authority for telecommunications
- Federal Communications Commission (FCC) – Federal telecommunications regulations
- National Institute of Standards and Technology (NIST) – Official U.S. time standards
Stay informed about area code changes and telecommunications updates to ensure your business and personal communications remain uninterrupted.