US Time Zones by State

Last reviewed on October 3, 2026

Most US states sit cleanly inside one time zone, but thirteen of them are officially split across two. This page lists where every state and the District of Columbia falls, then walks through the split states one by one, including where the zone line actually runs.

Throughout, "primary" zone means the zone covering most of the state's land area or population. For the split states, the secondary zone is noted with the area it covers. For interactive use, the map on the homepage shows approximate boundaries.

All 50 states and DC at a glance

Every state observes daylight saving time except Arizona (outside the Navajo Nation) and Hawaii. Click a zone for its live clock and full details.

States grouped by primary zone

The thirteen split states, one by one

The list below describes where the time zone line runs in each split state. Local airports, post offices, and major highways are useful landmarks, but county lines are typically the legal boundary.

Florida

Most of Florida is on Eastern Time. The western panhandle — including Pensacola, Fort Walton Beach and Panama City — is on Central Time. For most of its length the line follows the Apalachicola River, so Tallahassee, just to the east, is on Eastern Time.

Indiana

Indiana is mostly Eastern Time, but twelve counties are on Central Time: six in the northwest near Chicago (Lake, Porter, LaPorte, Newton, Jasper and Starke) and six in the southwest around Evansville (Gibson, Posey, Vanderburgh, Warrick, Spencer and Perry). Indiana's relationship with DST has changed several times since the Uniform Time Act; the whole state has observed daylight saving time since 2006.

Kansas

Kansas is mostly Central Time. Four counties in the far west — Sherman, Wallace, Greeley, and Hamilton — are on Mountain Time, matching their economic ties to Colorado.

Kentucky

Kentucky is split almost in half. The eastern part, including Louisville and Lexington, is on Eastern Time. The western part, including Bowling Green and Paducah, is on Central Time. The dividing line follows county boundaries and roughly bisects the state.

Michigan

Michigan is mostly Eastern Time, but four counties in the western Upper Peninsula — Gogebic, Iron, Dickinson, and Menominee — are on Central Time, because they border Wisconsin and share its commercial orientation.

Nebraska

Nebraska is split west of about the 100th meridian. The eastern part, including Omaha and Lincoln, is on Central Time. The western part, including the Panhandle, is on Mountain Time.

North Dakota

North Dakota is mostly Central Time, including Fargo, Bismarck and Grand Forks. The southwestern corner of the state — including Dickinson and Bowman, plus the southern part of McKenzie County — is on Mountain Time.

Oregon

Oregon is mostly Pacific Time. Most of Malheur County in the far southeast (including Ontario) is on Mountain Time, aligned with nearby Boise, Idaho; a small southern part of the county stays on Pacific Time.

South Dakota

South Dakota is split along the Missouri River. The eastern half, including Sioux Falls and Pierre, is on Central Time. The western half, including the Black Hills and Rapid City, is on Mountain Time.

Tennessee

Tennessee is mostly Central Time, including Nashville and Memphis, but East Tennessee — including Knoxville, Chattanooga and the Tri-Cities — is on Eastern Time. Drivers on I-40 cross the line on the Cumberland Plateau between Crossville (Central) and the Knoxville area (Eastern).

Texas

Texas is mostly Central Time. El Paso, in the far west, is on Mountain Time, along with neighbouring Hudspeth County (part of Culberson County also follows Mountain Time informally). This means El Paso runs an hour behind the rest of Texas year-round.

Idaho

Idaho is split between Mountain Time (the southern majority, including Boise and Idaho Falls) and Pacific Time (the northern Panhandle, including Coeur d'Alene). The line follows the Salmon River drainage. Travellers driving north on US-95 cross the zone change near Riggins.

Alaska

Most of Alaska is on Alaska Time, but the Aleutian Islands west of 169°30′ W — including Atka and Adak — are on Hawaii-Aleutian Time, one hour behind. Unlike Hawaii, this area observes daylight saving time. The International Date Line bends westward around the end of the island chain.

A note on Nevada

Nevada is usually counted as a single-zone Pacific state, but the border city of West Wendover uses Mountain Time to match neighbouring Wendover, Utah, and a few small communities near the Idaho line, such as Jackpot, informally do the same. Counting it, fourteen states have more than one time zone in use.

A comparison: travelling I-90 east to west

A practical way to see how the zones stack up is to follow a coast-to-coast highway. Travelling Interstate 90 from Boston, Massachusetts to Seattle, Washington, you change zones three times:

• Boston → Buffalo → Cleveland → Toledo: Eastern Time.
• Across northern Indiana on the Indiana Toll Road: Eastern Time until LaPorte County, where Central Time begins (LaPorte, Porter and Lake counties are on Central).
• Chicago → Wisconsin → southern Minnesota → eastern South Dakota: Central Time.
• Partway across South Dakota, between the Missouri River and the Badlands: Mountain Time begins, continuing through the Black Hills, Wyoming and Montana.
• Over Lookout Pass into the Idaho Panhandle, then Washington State: Pacific Time.

Common questions about state lines

How is the zone of a specific city decided?

The US Department of Transportation has authority over time zone boundaries under the Uniform Time Act of 1966. Counties (or in some cases parts of counties) can petition to switch zones, and the department evaluates each request on its commercial and social ties to neighbouring areas. Switches are uncommon but do happen.

Do federal facilities follow state time?

Generally yes — federal facilities use the local civil time of the county they are in. The exception is some military installations, which may observe Zulu (UTC) for operational purposes alongside local time.

What about reservations and tribal lands?

Tribal nations are sovereign and set their own observance. The most well-known case is the Navajo Nation, which observes daylight saving time even where it lies within Arizona, while the Hopi Reservation inside the Navajo Nation does not. For more on DST observance, see the daylight saving time page.

Use the converter

To check exactly how a meeting time in one state lands in another, the time converter on the homepage handles the math, and the business hours calculator finds overlap windows. For the abbreviations attached to each zone (EST vs. EDT, CT vs. CST, and so on), see the abbreviations guide. For information on Puerto Rico, Guam, and the other US territories — which sit outside the fifty-state list — see the territories page.