Which Indiana Counties Are in Central Time?
Twelve Indiana counties use Central Time. The state government lists six in northwest Indiana and six in southwest Indiana. Every other Indiana county uses Eastern Time.
Northwest IndianaJasper, Lake, LaPorte, Newton, Porter and Starke.
Southwest IndianaGibson, Perry, Posey, Spencer, Vanderburgh and Warrick.
All remaining countiesThe other 80 counties use Eastern Time, including Marion County (Indianapolis).
Where Is the Eastern–Central Boundary in Indiana?
The legal boundary follows county lines rather than a simple longitude. Under 49 CFR §71.5(b), the line crosses northern Indiana along LaPorte, Starke, Marshall, Pulaski, Jasper and Newton County boundaries, then follows the Illinois state line south before wrapping around the southwest Central Time counties near Gibson, Warrick, Spencer and Perry.
The regulation also states that municipalities located directly on the described boundary line are assigned to Central Standard Time. For trip planning near the boundary, the county or exact city matters more than a broad “north” or “south” label.