Area Code 423
Tennessee
Geographic Coverage
State
TN
Major Cities
- Chattanooga
- Johnson City
- Kingsport
- Cleveland
- Morristown
- Bristol
- East Ridge
- Greeneville
- Elizabethton
- Athens
- Soddy-Daisy
- Red Bank
- Middle Valley
- Collegedale
- Signal Mountain
- Bloomingdale
- Harrison
- South Cleveland
- La Follette
- Dayton
- Church Hill
- Newport
- Sweetwater
- Jonesborough
and 108 more cities
Time Zones
- Central Time (CT)
- Eastern Time (ET)
Current Time
This area code spans multiple time zones.


Demographics & Economics
- Total Population
- 2,359,591
- Population Density
- 115 people/sq miabove U.S. average (U.S.: 94 people/sq mi)
- Median Household Income
- $57,408below U.S. median (U.S.: $78,538)
- Poverty Rate
- 16.0%above U.S. average (U.S.: 12.4%)
- Unemployment Rate
- 5.4%near U.S. average (U.S.: 5.2%)
- Education Attainment
- Bachelor's Degree+23.0%below U.S. average (U.S.: 35.0%)High School or Lower40.2%
Statistics are population-weighted aggregations from Census ACS 5-year estimates.See Sources for details.
Overlay Area Code
This area code is part of an overlay region, meaning the same geographic area is served by multiple area codes. Overlay codes were introduced to meet growing demand for phone numbers without requiring existing customers to change their numbers.
This area code shares its geographic region with: area code 729.
In service since: 11-Sep-1995
Area Code Splits
Parts of this area code’s original geographic region were later assigned new area codes through splits. When a split occurs, some customers in the original area code region are assigned the new area code.
Split into: area code 865.
Call Context
This area code covers multiple cities and communities across a broad region in Tennessee. The region spans Central and Eastern time zones.
County Coverage
Population-weighted county share based on aggregated ZCTA population (100% = total mapped population for area code 423).
| County | Population | Share |
|---|---|---|
| Hamilton, TN | 418,151 | 17.7% |
| Sullivan, TN | 217,891 | 9.2% |
| Washington, TN | 192,282 | 8.1% |
| Hawkins, TN | 126,241 | 5.4% |
| Carter, TN | 124,281 | 5.3% |
| Bradley, TN | 120,885 | 5.1% |
| McMinn, TN | 98,617 | 4.2% |
| Unicoi, TN | 94,681 | 4.0% |
| Bledsoe, TN | 90,392 | 3.8% |
| Greene, TN | 84,366 | 3.6% |
| Sequatchie, TN | 71,280 | 3.0% |
| Marion, TN | 68,947 | 2.9% |
| Cocke, TN | 67,202 | 2.8% |
| Hamblen, TN | 66,080 | 2.8% |
| Monroe, TN | 55,771 | 2.4% |
| Polk, TN | 55,266 | 2.3% |
| Campbell, TN | 47,180 | 2.0% |
| Rhea, TN | 40,179 | 1.7% |
| Jefferson, TN | 39,592 | 1.7% |
| Claiborne, TN | 38,906 | 1.6% |
| Scott, TN | 25,724 | 1.1% |
| Van Buren, TN | 24,160 | 1.0% |
| Meigs, TN | 23,801 | 1.0% |
| Loudon, TN | 22,760 | 1.0% |
| Roane, TN | 20,574 | 0.9% |
| Johnson, TN | 19,242 | 0.8% |
| Morgan, TN | 19,065 | 0.8% |
| Hancock, TN | 18,324 | 0.8% |
| Scott, VA | 14,491 | 0.6% |
| Cumberland, TN | 13,012 | 0.6% |
| Union, TN | 12,449 | 0.5% |
| Sevier, TN | 7,430 | 0.3% |
| Franklin, TN | 6,604 | 0.3% |
| Lee, VA | 6,160 | 0.3% |
| Grainger, TN | 4,156 | 0.2% |
| Fentress, TN | 2,313 | 0.1% |
| Anderson, TN | 1,136 | 0.0% |
Nearby Area Codes
Area codes geographically closest to 423.
Frequently Asked Questions
Common questions about area code 423 and how phone numbering works.
Phone numbers are assigned based on where the number was originally provisioned, not the caller's current location. Mobile phones retain their number when users move, and businesses may use numbers from regions where they don't have a physical presence. VoIP services can also provision numbers from virtually any area code.
Yes, mobile phones can have numbers from any area code in the region they were activated. Wireless carriers assign numbers from available pools regardless of phone type. When users change carriers or move to new areas, they typically keep their original number, which may have a different area code than their current location.
Start by looking up the area code on this site to understand its general geographic region. For the specific number, options include using your carrier's caller ID features or checking public directories. If you suspect fraud, you can report it to the FTC. To file a complaint about robocalls or spoofed numbers, visit the FCC Consumer Complaint Center. You can also register your number with the National Do Not Call Registry to reduce unwanted calls. Keep in mind that caller ID can display any name the caller chooses to set.
When an area's pool of available phone numbers runs low, regulators may introduce an "overlay" area code that covers the same geographic territory as the original. Both codes coexist, and new numbers are assigned from whichever code has availability. Learn more in our overlay vs split guide.
While Cleveland is a prominent city in this area code's coverage, the code serves the broader surrounding region as well. Area codes are assigned geographically and typically cover multiple cities, towns, and communities beyond any single anchor city.







