The Pacific Time Zone (PT) is a

time zone A time zone is an area which observes a uniform standard time for legal, Commerce, commercial and social purposes. Time zones tend to follow the boundaries between Country, countries and their Administrative division, subdivisions instead of ...

encompassing parts of western Canada, the western United States, and western Mexico. Places in this zone observe

standard time Standard time is the synchronization of clocks within a geographical region to a single time standard, rather than a local mean time standard. Generally, standard time agrees with the local mean time at some meridian that passes through the r ...

by subtracting eight hours from

Coordinated Universal Time Coordinated Universal Time (UTC) is the primary time standard globally used to regulate clocks and time. It establishes a reference for the current time, forming the basis for civil time and time zones. UTC facilitates international communicat ...

( UTC−08:00). During

daylight saving time Daylight saving time (DST), also referred to as daylight savings time, daylight time (Daylight saving time in the United States, United States and Daylight saving time in Canada, Canada), or summer time (British Summer Time, United Kingdom, ...

, a time offset of UTC−07:00 is used. In the United States and Canada, this time zone is generically called the Pacific Time Zone. Specifically, time in this zone is referred to as Pacific Standard Time (PST) when standard time is being observed (early November to mid-March), and Pacific Daylight Time (PDT) when daylight saving time (mid-March to early November) is being observed. In

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

, the corresponding time zone is known as the ''Zona Noroeste'' (Northwest Zone) and observes the same daylight saving schedule as the United States and Canada. The largest city in the Pacific Time Zone is

Los Angeles Los Angeles, often referred to by its initials L.A., is the List of municipalities in California, most populous city in the U.S. state of California, and the commercial, Financial District, Los Angeles, financial, and Culture of Los Angeles, ...

, whose metropolitan area is also the largest in the time zone. The zone is two hours ahead of the

Hawaii–Aleutian Time Zone The Hawaii–Aleutian Time Zone observes Hawaii–Aleutian Standard Time (HST) by subtracting ten hours from Coordinated Universal Time ( UTC−10:00). The clock time in this zone is based on the mean solar time of the 150th meridian west of th ...

, one hour ahead of the

Alaska Time Zone The Alaska Time Zone observes standard time by subtracting nine hours from Coordinated Universal Time ( UTC−09:00). During daylight saving time its time offset is eight hours ( UTC−08:00). The clock time in this zone is based on mean sola ...

, one hour behind the

Mountain Time Zone The Mountain Time Zone of North America keeps time by subtracting seven hours from Coordinated Universal Time (UTC) when standard time ( UTC−07:00) is in effect, and by subtracting six hours during daylight saving time ( UTC−06:00). The ...

, two hours behind the

Central Time Zone The North American Central Time Zone (CT) is a time zone in parts of Canada, the United States The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It ...

, three hours behind the

Eastern Time Zone The Eastern Time Zone (ET) is a time zone encompassing part or all of 23 U.S. states, states in the eastern part of the United States, parts of eastern Canada, and the state of Quintana Roo in Mexico. * Eastern Standard Time (EST) is five ...

, and four hours behind the

Atlantic Time Zone The Atlantic Time Zone is a geographical region that keeps standard time—called Atlantic Standard Time (AST)—by subtracting four hours from Coordinated Universal Time ( UTC), resulting in UTC−04:00. AST is observed in parts of North America ...

Canada

One Canadian province is split between the Pacific Time Zone and the Mountain Time Zone: *

British Columbia British Columbia is the westernmost Provinces and territories of Canada, province of Canada. Situated in the Pacific Northwest between the Pacific Ocean and the Rocky Mountains, the province has a diverse geography, with rugged landscapes that ...

– all, except for the Highway 95 corridor (including Golden and Creston) in the southeast, and

Tumbler Ridge Tumbler Ridge is a district municipality in the foothills of the B.C. Rockies in northeastern British Columbia, Canada, and a member municipality of the Peace River Regional District. With a population of 2,399 (2021) living in a townsite, th ...

, Fort St. John, and

Dawson Creek Dawson Creek is a city in northeastern British Columbia, Canada. The municipality of had a population of 12,978 in 2016. Dawson Creek derives its name from the creek of the same name that runs through the community. The creek was named after ...

in the northeast The border between time zones in British Columbia was decided in a 1972 plebiscite held in northeastern and southeastern electoral districts due to their ties to neighboring

Alberta Alberta is a Provinces and territories of Canada, province in Canada. It is a part of Western Canada and is one of the three Canadian Prairies, prairie provinces. Alberta is bordered by British Columbia to its west, Saskatchewan to its east, t ...

. As of September 24, 2020,

Yukon Yukon () is a Provinces and territories of Canada, territory of Canada, bordering British Columbia to the south, the Northwest Territories to the east, the Beaufort Sea to the north, and the U.S. state of Alaska to the west. It is Canada’s we ...

officially switched from the Pacific Time Zone to a time zone "to be reckoned as seven hours behind Coordinated Universal Time (UTC−7)" after deciding to stop observing daylight saving time.

Mexico

, the ''Zona Noroeste'', which corresponds to Pacific Time in the United States and Canada, includes: *

Baja California Baja California, officially the Free and Sovereign State of Baja California, is a state in Mexico. It is the northwesternmost of the 32 federal entities of Mexico. Before becoming a state in 1952, the area was known as the North Territory of B ...

United States

Two states are fully contained in the Pacific Time Zone: *

California California () is a U.S. state, state in the Western United States that lies on the West Coast of the United States, Pacific Coast. It borders Oregon to the north, Nevada and Arizona to the east, and shares Mexico–United States border, an ...

* Washington Three states are split between the Pacific Time Zone and the

: *

Idaho Idaho ( ) is a landlocked U.S. state, state in the Pacific Northwest and Mountain states, Mountain West subregions of the Western United States. It borders Montana and Wyoming to the east, Nevada and Utah to the south, and Washington (state), ...

– 10 counties in the

Idaho Panhandle The Idaho panhandle—locally known as North Idaho, Northern Idaho, or simply the Panhandle—is a salient region of the U.S. state of Idaho encompassing the state's 10 northernmost counties: Benewah, Bonner, Boundary, Clearwater, Idaho, ...

north of Hells Canyon and the Salmon River observe Pacific time, due to proximity to cities in Washington *

Nevada Nevada ( ; ) is a landlocked state in the Western United States. It borders Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, and Utah to the east. Nevada is the seventh-most extensive, th ...

– all, except for West Wendover, due to proximity to

Wendover, Utah Wendover is a city on the western edge of Tooele County, Utah, Tooele County, Utah, United States. The population was 1,115 at the 2020 United States Census, 2020 census. Description Wendover is on the western border of Utah and is contiguous ...

and several towns along the Idaho border, including Jackpot, Jarbidge, Mountain City, and Owyhee. *

Oregon Oregon ( , ) is a U.S. state, state in the Pacific Northwest region of the United States. It is a part of the Western U.S., with the Columbia River delineating much of Oregon's northern boundary with Washington (state), Washington, while t ...

– all, except for the majority of Malheur County due to proximity to Idaho cities; it was moved in 1923 to accommodate the needs of the

Oregon Short Line Railroad The Oregon Short Line Railroad was a railroad in Wyoming, Idaho, Utah, Montana and Oregon in the United States. The line was organized as the Oregon Short Line Railway in 1881 as a subsidiary of the Union Pacific Railway. The Union Pacific int ...

. One state is split between the Pacific Time Zone (unofficially), the

, and the

: *

Alaska Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the north ...

– Hyder, unofficially uses Pacific time due to proximity to Stewart, British Columbia

Daylight saving time

Through 2006, the local time (PST, UTC−08:00) changed to daylight time (PDT, UTC−07:00) at 02:00 LST (local standard time) to 03:00 LDT (local daylight time) on the first Sunday in April, and returned at 02:00 LDT to 01:00 LST on the last Sunday in October. The

United States Congress The United States Congress is the legislature, legislative branch of the federal government of the United States. It is a Bicameralism, bicameral legislature, including a Lower house, lower body, the United States House of Representatives, ...

passed the

Energy Policy Act of 2005 The Energy Policy Act of 2005 () is a federal law signed by President George W. Bush on August 8, 2005, at Sandia National Laboratories in Albuquerque, New Mexico. The act, described by proponents as an attempt to combat growing energy problems ...

, which moved the local time changes from PST to PDT to the second Sunday in March and the reversal from PDT to PST to the first Sunday in November. Like other Canadian provinces that observe daylight time, British Columbia adopted the same dates in April 2006, to take effect in March 2007 alongside the U.S. Several Mexican states, including Baja California, implemented the new dates for the daylight time changes in 2010, ending a three-year period where cities across the

Mexico–United States border The international border separating Mexico and the United States extends from the Pacific Ocean in the west to the Gulf of Mexico in the east. The border traverses a variety of terrains, ranging from urban areas to deserts. It is the List of ...

had a one-hour difference for two months a year. Proposals to abolish the bi-annual time change and adopt year-round standard time or daylight time gained popularity among U.S. states in the 2010s. 59 percent of voters in California approved a 2018 ballot proposition that authorizes the legislature to use year-round daylight saving time, pending Congressional approval. The

Washington State Legislature The Washington State Legislature is the state legislature of the State of Washington. It is a bicameral body, composed of the lower Washington House of Representatives, composed of 98 representatives, and the upper Washington State Senate, w ...

passed a bill in May 2019 that would move the state to permanent daylight time, subject to Congressional approval; the

Oregon Legislative Assembly The Oregon Legislative Assembly is the State legislature (United States), state legislature for the U.S. state of Oregon. The Legislative Assembly is bicameral, consisting of an upper house, upper and lower chamber: the Oregon State Senate, Sena ...

passed a similar bill a month later, while California's attempt failed. The provincial government of British Columbia announced in 2019 that they would follow the U.S. states in whether the time changes were kept or removed in order to maintain a unified time zone. In 2020, Idaho passed legislation to allow for permanent daylight time for the Pacific Time Zone. Congressional approval was sought through the Sunshine Protection Act, which was submitted several times and passed by the U.S. Senate in 2022, but its equivalent in the

House of Representatives House of Representatives is the name of legislative bodies in many countries and sub-national entities. In many countries, the House of Representatives is the lower house of a bicameral legislature, with the corresponding upper house often ...

failed to pass.

Notes

References

External links

The Official NIST US Time

Official times across Canada

History of U.S. time zones and UTC conversion

{{Authority control Time in Canada Time in Mexico Time zones Time zones in the United States