Hamilton County · Tennessee
Chattanooga, TN area codes and time zone
Quick answer
Chattanooga is served by area code 423, keeps CST time (GMT-6), and sits in county FIPS 47065.
- Area code
- 423Within 25 miles of the city centre
- Time zone
- CSTAmerica/Chicago
- UTC offset
- GMT-6CDT in summer (UTCGMT-5)
- County FIPS
- 47065Hamilton County
Dialling from and to Chattanooga
What this means when you pick up the phone.
Local calls inside 423 may still work on seven digits, but ten-digit dialling is the safe default everywhere in the country now. From abroad, dial +1 then the ten digits.
How Chattanooga came to have one area code
Why one city can carry several codes.
Area codes are assigned to geography, then exhausted as demand grows. Chattanooga — population about 187k — is covered by code 423, drawn from within 25 miles of the city centre. A single code still has enough numbers for the area, so no overlay has been needed yet. When growth exhausts it, regulators will layer on a new code and local calls will move to ten digits.
More Chattanooga data
Other Chattanooga datasets on this site.
- Chattanooga population and income
- Chattanooga sales tax rate
- Chattanooga property tax
- Chattanooga cost of living
- Chattanooga home values and rent
- Chattanooga crime rates
- Chattanooga public schools
- Chattanooga weather normals
- Chattanooga commute times
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