The Pacific Time Zone observes standard time by subtracting eight hours from Coordinated Universal Time (UTC-8). During Daylight Saving Time, its time offset is UTC-7.

In the United States and Canada, this time zone is generically called Pacific Time (PT). Specifically, it is Pacific Standard Time (PST) when observing standard time (Winter), and Pacific Daylight Time (PDT) when observing daylight savings (Summer).

The zone is one hour ahead of the Alaska Time Zone and one hour behind the Mountain Time Zone.

In the United States, the states of Washington and California are located entirely within the Pacific Time Zone. Nearly all of Nevada, except for the town of West Wendover is on Pacific Time, although certain small towns near the Idaho border, such as Jackpot, observe Mountain Standard Time unofficially. Additionally, the northern part of Idaho (the Idaho Panhandle) and all of Oregon except for the greater part of Malheur County are also in the zone.

In Canada, it includes almost all of the province of British Columbia (except for the Highway 95 corridor and portions around Fort St. John), all of the Yukon Territory and Tungsten, Northwest Territories.

In Mexico, the state of Baja California is wholly within and the only part of Mexico in PST.

Most of the Pacific Time zone observes Pacific Daylight Time (PDT, UTC-7) during the summer months, with the exception of the areas surrounding Dawson Creek and Creston in British Columbia.

The local time (PST, UTC-8) changes to PDT (UTC-7) at 02:00 LST (local standard time) to 03:00 LDT (local daylight time) on the first Sunday in April, and returns at 02:00 LDT to 01:00 LST on the last Sunday in October.