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Pacific Time Zone

time zone observing UTC−08:00 during standard time and UTC−07:00 during daylight saving time

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General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionSep 20, 2026
Entity authorityQ847142 ↗
Source-derived summary

The Pacific Time Zone (PT) is a time zone encompassing the western United States and northwestern Mexico. Places in this zone observe standard time by subtracting eight hours from Coordinated Universal Time (UTC−08:00). During daylight saving time, a time offset of UTC−07:00 is used instead.

In the United States, 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, the corresponding time zone is known as the Zona Noroeste (lit. 'Northwest Zone') and observes the same daylight saving schedule as the United States. The largest city in the Pacific Time Zone is 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, one hour ahead of the Alaska Time Zone, one hour behind the Mountain Time Zone, two hours behind the Central Time Zone, three hours behind the Eastern Time Zone, and four hours behind the Atlantic Time Zone.

Canada

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 neighbouring Alberta.

In March 2020, the Canadian territory of Yukon abolished Pacific Standard Time and adopted daylight saving time (UTC−07:00) year-round.

Editorial summary

Begin with the source’s own compact description: “Pacific Time Zone” is time zone observing UTC−08:00 during standard time and UTC−07:00 during daylight saving time. The dossier treats that line as a proposition to test through Pacific, Time and Zone, not as a finished interpretation.

Editorial reviewA practical starting point whose main value is the path it opens into stronger specialist and primary sources. The current lead gives the account dated anchors—1972, 2020—that can be checked directly. The selected authority fields contribute no independent date. For this dossier, Pacific, Time and Zone is the immediate research focus.
Editorial analysis

Why this record matters

The phrase “time zone observing UTC−08:00 during standard time and UTC−07:00 during daylight saving time” supplies a clear boundary for inquiry. It also exposes the unanswered questions: who defined that boundary, when it became stable and which sources sit outside it.

Evidence profile

Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Sep 20, 2026. The linked authority identifier is Q847142. The first chronological checks are 1972 and 2020.

Critical limits

A concise general-reference account can conceal disagreements about scope, terminology or the weight assigned to individual sources. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.

How to read it

Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.

Best used for
  • Subject orientation
  • Search vocabulary
  • Locating named sources
Verify next

The closest primary source, responsible institution and strongest cited specialist reference.

Three-step research path

  1. Establish the record: confirm the title “Pacific Time Zone”, its source revision and the description used here.
  2. Expand the search: follow Pacific Time Zone primary sources, Pacific Time Zone archive and Pacific research across catalogues and specialist indexes.
  3. Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.

Questions for further research

  1. Which source most directly establishes the central claim about “Pacific Time Zone”?
  2. Which institution is responsible for the underlying evidence?
  3. Which cited source is closest to the event, object or claim?
Subject index

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Source & attribution

This entry incorporates text from “Pacific Time Zone” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.