What is the time zone of Idaho?

The state of Idaho is divided into two time zones. Most northern part above the salmon river, covering 10 counties and 25% of the state, is in the Pacific Time zone and observing daylight savings so there are two different clocks depending on the time of year. 

  • (PST) Pacific Standard Time: – 8:00 UTC/GMT (behind)
  • (PDT) Pacific Daylight Time: – 7:00 UTC/GMT (behind)

Majority of Idaho below the salmon river is in the Mountain Time zone and also observing daylight savings so there are two different clocks depending on the time of year. 

  • (MST) Mountain Standard Time: – 7:00 UTC/GMT (behind)
  • (MDT) Mountain Daylight Time: – 6:00 UTC/GMT (behind)
Pacific Time
Mountain Time
USA time zone map 1
Click to enlarge
us state Idaho counties time zone map
Idaho time zone

It can be complicated when crossing state borders. Neighbouring states of Utah, Wyoming and Montana observe Mountain Time, while Washington and Nevada observe Pacific Time. Given the fact that Idaho has dual time zones you can enter a different time zone depending on the location of your border crossing.

When you cross the Canadian border, you will remain in the same Pacific time zone.

Zone boundary

There is a clear physical boundary of time zones being salmon river.

Idaho time zone border
Idaho time zone border

The official border is defined in the Code of Federal Regulations (CFR) §71.9. (a):

Idaho Code of Federal Regulations

Idaho Daylight savings time (DST)

The state of Idaho is using daylight savings as also documented in the Uniform Time Act of 1966. During daylight savings the time changes from Standard time to Daylight time, so PST becomes PDT and MST becomes MDT depending on your location. 

It starts on the second Sunday in March and ends on the first Sunday in November. In March the clock is moved forward from 02.00 am to 03.00 am (so you will lose an hour of sleep during the night). While in November it’s reversed as the clock is moved backward from 03.00 am to 02.00 am and you will gain an extra hour of sleep. One way of remembering the movement sequence is that clocks “spring forward and fall back”.

The total period of daylight savings lasts for 34 weeks which is about 65% of the year.

Idaho time news, bills and legislation

There is a continuous debate about which time should be applied. Several state bills have been introduced to legalize daylight saving time as the year-round clock, whereas others try to align the time with bordering counties or states. The table below gives an overview of the latest bills in the state of Idaho.

Date Bill Status/Action Title/summary
19 Mar 2020 S1386 Engross, U.C. to be returned to State Affairs Committee daylight saving time -- Adds to existing law to provide that certain areas of the State of Idaho shall make daylight saving time the permanent time upon a specified condition.
16 Mar 2020 S1267 Pass, Session Law Chapter 145 Effective: 07/01/2020 Contingent on legislation approved by the state of Washington. daylight saving time -- Adds to existing law to provide that certain areas of the State of Idaho shall make daylight saving time the permanent time upon a specified condition.
6 Feb 2020 H0358 Intro, U.C. to be returned to State Affairs Committee daylight saving time -- Adds to existing law to provide that the State of Idaho shall be exempt from the daylight saving time provisions of federal law.

Other US states

You can check out information and maps of other US states by clicking on the below links.