States on Eastern Time
Every full and split state, with capitals and Central Time neighbours.
Split state · 80 counties ET · 12 counties CT
Indiana keeps Eastern Time in 80 of its 92 counties. Twelve – six in the Chicago area and six around Evansville – use Central Time, and since April 2, 2006 the whole state observes daylight saving time.
Two corners of the state follow Central Time. In the northwest, part of the Chicago metropolitan area: Lake, Porter, LaPorte, Starke, Jasper and Newton counties. In the southwest, around Evansville: Gibson, Posey, Vanderburgh, Warrick, Spencer and Perry counties.
That puts Gary, Hammond, Valparaiso, Michigan City and Evansville on CT. Indianapolis, Fort Wayne, South Bend, Lafayette, Bloomington and Terre Haute are on Eastern Time, as are the five counties that went to Central Time in 2006 and came back in 2007.
Two names trip people up. Knox is both the county seat of Starke County (Central) and a separate county around Vincennes (Eastern). Jasper is a Central Time county in the northwest, but the city of Jasper, seat of Dubois County, is on Eastern Time.
| Region | County | County seat |
|---|---|---|
| Northwest | Lake | Crown Point |
| Northwest | Porter | Valparaiso |
| Northwest | LaPorte | La Porte |
| Northwest | Starke | Knox |
| Northwest | Jasper | Rensselaer |
| Northwest | Newton | Kentland |
| Southwest | Gibson | Princeton |
| Southwest | Posey | Mount Vernon |
| Southwest | Vanderburgh | Evansville |
| Southwest | Warrick | Boonville |
| Southwest | Spencer | Rockport |
| Southwest | Perry | Tell City |
The boundary in 49 CFR § 71.5(b) is built entirely from county lines:
The northwest corner borders Illinois, and the southwest corner borders Illinois and western Kentucky across the Ohio River – all on Central Time – while Ohio, southern Michigan and the Louisville side of Kentucky use Eastern Time. The time zone boundaries guide follows the line the rest of the way to the Gulf.
Violet: Central Time county seats. Amber: Eastern Time cities, including the seats of the counties that switched back in 2007.
By longitude, Indiana is a Central Time state. Indianapolis sits at 86.1°W, much closer to the Central meridian (90°W) than the Eastern one (75°W), so on Eastern Time the sun's mean noon there comes at about 12:45 PM EST. When the federal government first drew zones in 1918, all of Indiana was on Central Time. The Interstate Commerce Commission moved the eastern half to Eastern Time in 1961, and the US Department of Transportation put everything except six northwestern and six southwestern counties on Eastern Time effective April 27, 1969.
Federal law lets a state that spans two zones skip daylight saving time in one of them, and Indiana did exactly that. From the early 1970s through 2005 the Eastern portion stayed on EST all year while the Central counties changed clocks like Chicago. The result, as DOT put it, was that most of Indiana matched New York in winter and Chicago in summer. Five counties near Louisville and Cincinnati – Clark, Floyd, Harrison, Dearborn and Ohio – set their clocks to daylight time anyway, unofficially, to stay in step with their metro areas.
Along the way, Pike County moved from Central to Eastern Time in 1977 and Starke County did the same in 1991, leaving ten Central Time counties by 2005. The history of Eastern Time covers the federal laws behind this patchwork.
In 2005 the General Assembly passed Senate Enrolled Act 127, which put the entire state on daylight saving time from 2006. The same law asked DOT to hold hearings on where the Eastern–Central line should run in Indiana, and said the state would support any county that petitioned to change zones.
Nineteen counties asked to move to Central Time; two withdrew. In a final rule published on January 20, 2006, DOT moved eight of them – Starke and Pulaski in the northwest and Knox, Daviess, Martin, Pike, Dubois and Perry in the southwest – effective at 2:00 AM on April 2, 2006, the night DST began. It turned down the rest, including St. Joseph County (South Bend).
For almost a year Indiana had 18 Central Time counties. Then several asked to go back.
| Effective | Counties | Change | Central Time counties after |
|---|---|---|---|
| April 2, 2006 | Starke, Pulaski, Knox, Daviess, Martin, Pike, Dubois, Perry | Eastern → Central | 18 |
| March 11, 2007 | Pulaski | Central → Eastern | 17 |
| November 4, 2007 | Knox, Daviess, Martin, Pike, Dubois | Central → Eastern | 12 |
Pulaski County petitioned on February 7, 2006 – before its move had even taken effect – and returned to Eastern Time on March 11, 2007. Knox, Daviess, Martin, Pike and Dubois filed a joint petition in August 2006 and went back at 2:00 AM CDT on November 4, 2007, when DST ended. In the same September 2007 rule, DOT denied Perry County's request to return as well, ruling that the county had not shown the move would serve the convenience of commerce. Perry and Starke are the two counties that stayed, which is how the count settled at twelve. The boundary has not moved since.
Driving north from Evansville toward Indianapolis, clocks jump ahead one hour where you cross into Knox, Pike or Dubois County. For a quick ET/CT table, use the EST to CST converter; the live Eastern Time clock shows Indianapolis time.
Phones and computers use the IANA time zone database, which keeps a separate entry for every area with its own clock history since 1970. Indiana has eight under America/Indiana/: Indianapolis, Knox (Starke County), Marengo (eastern Crawford County), Petersburg (Pike), Tell_City (Perry), Vevay (Switzerland County), Vincennes (Daviess, Dubois, Knox and Martin) and Winamac (Pulaski). Today all show Eastern Time except Knox and Tell_City, which show Central; the separate names keep past timestamps, such as July 2006 in Petersburg, correct.
Vincennes (Eastern) and Evansville (Central) are about 48 miles apart. On December 21, 2026 the sun rises at 8:04 AM EST in Vincennes and 7:03 AM CST in Evansville; on June 21, 2027 it sets at 9:18 PM EDT in Vincennes and 8:16 PM CDT in Evansville.
Western Kentucky and four Upper Peninsula counties in Michigan also keep Central Time; all states on Eastern Time lists the rest.
Yes. Gary and Hammond are in Lake County, Indiana, which is on Central Time, so their clocks always match Chicago's – and run one hour behind Indianapolis.
No. Evansville (Vanderburgh County) is on Central Time, while Louisville across the Ohio River upstream is on Eastern Time, so Louisville is one hour ahead all year.
Central Time. The town of Santa Claus is in Spencer County, one of the six southwestern counties on Central Time, so park hours are listed in CT.
Yes. South Bend (St. Joseph County), West Lafayette (Tippecanoe County) and Bloomington (Monroe County) are all on Eastern Time, like Indianapolis.
Yes. Michigan City is in LaPorte County and the Indiana Dunes lie in Lake, Porter and LaPorte counties, all on Central Time. Driving east into St. Joseph County toward South Bend, clocks jump ahead one hour.
Every full and split state, with capitals and Central Time neighbours.
The 41 western Kentucky counties across the Ohio River on Central Time.
The four Upper Peninsula counties that share Wisconsin's clock.
How DOT decides where the Eastern–Central line runs.
Indianapolis to Evansville time, hour by hour.
From railroad time in 1883 to the Uniform Time Act.