Split state · Eastern + Central

Tennessee time zones

East Tennessee's 30 easternmost counties – Knoxville, Chattanooga and the Tri-Cities – use Eastern Time. Nashville, Memphis and the other 65 counties use Central Time, one hour behind.

Knoxville & Chattanooga (ET)
--:-- ET
Nashville & Memphis (CT)
--:-- CT
Counties on Eastern Time
30 of 95
Next clock change
Second Sunday in March

Which Tennessee counties are on Eastern Time?

Thirty counties, all in the state's eastern end. The federal boundary in 49 CFR §71.5(d) starts at the Kentucky line and runs south along the west line of Scott County, the north and west lines of Morgan County and the north line of Roane County, then along the north and west lines of Rhea County and the west line of Hamilton County to Georgia. Every county east of that line keeps the same clock as the live Eastern Time clock:

Anderson, Blount, Bradley, Campbell, Carter, Claiborne, Cocke, Grainger, Greene, Hamblen, Hamilton, Hancock, Hawkins, Jefferson, Johnson, Knox, Loudon, McMinn, Meigs, Monroe, Morgan, Polk, Rhea, Roane, Scott, Sevier, Sullivan, Unicoi, Union and Washington.

Not all of East Tennessee is on Eastern Time. State law counts 33 counties in the East Tennessee Grand Division, and three of them – Bledsoe, Cumberland and Marion – observe Central Time. So do their neighbours Sequatchie, Fentress and Pickett. Marion and Sequatchie belong to the Chattanooga metropolitan area, so commuters into Chattanooga from Jasper, South Pittsburg or Dunlap cross a time zone on the way to work.

The 30 Eastern Time counties and their county seats
CountySeatCountySeat
AndersonClintonKnoxKnoxville
BlountMaryvilleLoudonLoudon
BradleyClevelandMcMinnAthens
CampbellJacksboroMeigsDecatur
CarterElizabethtonMonroeMadisonville
ClaiborneTazewellMorganWartburg
CockeNewportPolkBenton
GraingerRutledgeRheaDayton
GreeneGreenevilleRoaneKingston
HamblenMorristownScottHuntsville
HamiltonChattanoogaSevierSevierville
HancockSneedvilleSullivanBlountville
HawkinsRogersvilleUnicoiErwin
JeffersonDandridgeUnionMaynardville
JohnsonMountain CityWashingtonJonesborough

Why is East Tennessee on Eastern Time?

Tennessee has always thought of itself in three parts. The Grand Divisions – East, Middle and West Tennessee – are written into state law (Tennessee Code Title 4, Chapter 1, Part 2) and are the three stars on the state flag. They follow geography: the Appalachian ridges and the Great Valley in the east, the Nashville Basin in the middle, and the Mississippi lowlands in the west. The Cumberland Plateau, a long tableland rising hundreds of feet above the valleys on either side, separates East from Middle Tennessee, and the time zone line runs across it.

That landscape shapes trade. The Great Valley runs northeast to southwest, so East Tennessee's natural partners are Virginia, the Carolinas and Georgia – all on Eastern Time – rather than Nashville on the far side of the plateau. Bristol is split between Tennessee and Virginia down the middle of State Street, and Chattanooga's metro area spills into north Georgia, about two hours' drive from Atlanta on I-75.

Before the late 1940s, though, the whole state was in the Central zone. During World War II the country ran on year-round "war time", and when it ended, Knoxville did not want to give up the later daylight. According to contemporary Knoxville Journal reports, Mayor Cas Walker proclaimed Eastern Standard Time from April 1946, Maryville and Oak Ridge followed, and in 1949 the Interstate Commerce Commission, then responsible for time zones, moved the federal boundary so that Chattanooga joined the Eastern zone too. The line has since settled on county borders that mirror the plateau. For how boundary requests work today, see our guide to time zone boundaries.

Where exactly does the time line run in Tennessee?

On the plateau's northern section, Scott and Morgan counties are on Eastern Time while Fentress and Cumberland, just to the west, are on Central. Farther south the line follows the edge of the Sequatchie Valley: Rhea and Hamilton are Eastern, while Bledsoe, Sequatchie and Marion are Central. Longitude barely matters here – Crossville (Central) actually sits slightly east of Chattanooga (Eastern).

Drivers notice the switch on the interstates. On I-40 the clock falls back an hour as you climb from Roane County onto the plateau in Cumberland County; on I-24 it changes west of Chattanooga at the Marion County line. North of the state line, the same boundary continues through Kentucky – see the Kentucky time zone page – and to the south it follows the Georgia–Alabama border, which keeps Atlanta on Eastern Time.

Solar time explains why the arrangement is comfortable for East Tennessee. Knoxville lies at about 84°W, close to the 82.5°W edge of the ideal Eastern band, so in winter its clock runs only about 35–40 minutes ahead of the sun. Memphis, near 90°W, is almost exactly on the meridian that defines Central Time.

Solar noon and sunset (computed for Dec 21, 2026 and Jun 21, 2027)
CityZoneSolar noon Dec 21Solar noon Jun 21Sunset Jun 21
BristolET12:28 PM EST1:31 PM EDT8:51 PM EDT
KnoxvilleET12:35 PM EST1:38 PM EDT8:56 PM EDT
ChattanoogaET12:40 PM EST1:43 PM EDT8:59 PM EDT
CrossvilleCT11:39 AM CST12:43 PM CDT8:01 PM CDT
NashvilleCT11:46 AM CST12:50 PM CDT8:08 PM CDT
MemphisCT11:59 AM CST1:02 PM CDT8:18 PM CDT

How do you schedule across Tennessee's two time zones?

Assume a one-hour gap: 9:00 AM in Knoxville is 8:00 AM in Nashville, all year. Both halves of the state observe daylight saving time on the same Sundays, the second Sunday in March and the first Sunday in November, so the difference never changes except for one hour on each transition night, because each zone switches at 2:00 AM local time. Organisations based in Nashville or Memphis normally quote Central Time, and those in Knoxville or Chattanooga quote Eastern. When a time is written without a zone, ask. The EST to CST converter handles the arithmetic, and the states on Eastern Time hub compares Tennessee with the other split states.

Frequently asked questions

Are Gatlinburg and the Great Smoky Mountains on Eastern Time?

Yes. Gatlinburg and Pigeon Forge are in Sevier County, which is on Eastern Time, and Great Smoky Mountains National Park is on Eastern Time on both the Tennessee and North Carolina sides.

What time zone is Oak Ridge in?

Eastern Time. Oak Ridge lies in Anderson and Roane counties, both east of the time zone line, so it keeps the same clock as Knoxville.

Which Tennessee airports are on Eastern Time?

Knoxville's McGhee Tyson Airport (TYS), Chattanooga Metropolitan Airport (CHA) and Tri-Cities Airport (TRI) are on Eastern Time. Nashville (BNA) and Memphis (MEM) are on Central Time, so a flight from Knoxville to Nashville lands at an earlier clock time than its flight length suggests.

Which IANA time zone IDs does Tennessee use?

America/New_York for the Eastern Time counties and America/Chicago for the Central Time counties. Tennessee has no zone ID of its own because its time zone changes all happened before 1970, the year from which the database gives every region with a distinct clock history its own ID.

Will Tennessee switch to permanent daylight saving time?

Only if Congress allows it. A 2019 state law (Public Chapter 416) would keep Tennessee on daylight time all year once federal law permits. The federal Sunshine Protection Act (H.R. 139) passed the House 308–117 on July 14, 2026, but as of November 2026 the Senate has not voted on it, so both halves of Tennessee still change clocks twice a year.

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