.png)
Idaho Falls operates on the Mountain Time Zone, shifting between Mountain Standard Time (MST) and Mountain Daylight Time (MDT) depending on the time of year. If you're trying to figure out what time it is right now or how the local clocks operate, understanding this split is essential.
The city observes Daylight Saving Time (DST), matching the federal standard observed across most of the United States. Read on to find out how offsets work, when the clocks change, and why Idaho's unique geographic split causes frequent confusion.
Idaho Falls Time Zone Basics
Idaho Falls is located in Bonneville County in eastern Idaho. Like the vast majority of the state south of the Salmon River, it falls within the Mountain Time Zone.
Depending on the season, the local offset from Coordinated Universal Time (UTC) changes by one hour:
- Mountain Standard Time (MST): Used during the late fall and winter months. The offset is UTC-7.
- Mountain Daylight Time (MDT): Used during the spring, summer, and early fall months. The offset is UTC-6.
For official scheduling, computer systems and servers typically reference the IANA time zone identifier America/Boise for this region. You can check official shifts via the National Institute of Standards and Technology to ensure your devices sync properly.
Daylight Saving Time Schedule
Idaho Falls follows the Energy Policy Act of 2005 guidelines for Daylight Saving Time. This means clocks do not change on arbitrary dates; instead, they follow a fixed weekend schedule each spring and autumn.
Spring Forward
On the second Sunday in March at 2:00 AM local time, clocks move forward by one hour. This transitions the city from MST (UTC-7) to MDT (UTC-6), resulting in an hour less of sleep but longer evening daylight.
Fall Back
On the first Sunday in November at 2:00 AM local time, clocks move backward by one hour. This shifts the city back from MDT to MST, returning the local offset to UTC-7.
The Unique State Split: Mountain vs. Pacific Time
Travelers often assume an entire state shares a single time zone, but Idaho is split cleanly down the middle. This geographic quirk trips up visitors crossing the state.
- Northern Idaho (The Panhandle): Counties north of the Salmon River—including Coeur d'Alene, Lewiston, and Sandpoint—observe Pacific Time (PST/PDT, UTC-8/-7).
- Southern and Eastern Idaho: Cities south of that line, including Idaho Falls, Boise, Pocatello, and Twin Falls, observe Mountain Time (MST/MDT).
Driving north from Idaho Falls toward the Canadian border means crossing a time zone boundary. You'll lose an hour if you head north into the Panhandle, and gain an hour if you return south. You can review regional maps and boundary details directly through the U.S. Department of Transportation.
Common Mistakes When Calculating Time
People scheduling calls or travel to eastern Idaho frequently make a few predictable errors. Avoid these missteps to keep your plans on track:
- Assuming all of Idaho is on Mountain Time: Forgetting about the northern Panhandle leads to missed meetings or late arrivals if you assume a statewide uniform time.
- Ignoring the transition weekend: The U.S. shifts clocks on different dates than some international countries. If you are coordinating across borders during March or November, double-check the exact transition weekends.
- Forgetting the offset math with the East Coast: Idaho Falls is 2 hours behind New York (Eastern Time) and 1 hour behind Chicago (Central Time), regardless of whether standard or daylight time is active, because both regions observe DST concurrently.
Frequently Asked Questions
Does Idaho Falls stay on Mountain Time all year?
No. While it stays within the Mountain Time zone designation, it observes Daylight Saving Time. It uses Mountain Standard Time in the winter and Mountain Daylight Time in the summer.
What is the time difference between Idaho Falls and Boise?
There is no time difference between Idaho Falls and Boise. Both cities sit within the southern/eastern half of Idaho and share the exact same Mountain Time rules.
When do the clocks change in Idaho Falls?
Clocks move forward an hour on the second Sunday of March and fall back an hour on the first Sunday of November. The change always occurs officially at 2:00 AM local time.
How far ahead or behind is Idaho Falls from UTC?
Idaho Falls is UTC-7 during standard time (winter) and UTC-6 during daylight saving time (summer).
