How many hours ahead is MST compared to PST?

Mountain Standard Time is 1 hour ahead of Pacific Standard Time during winter. In summer both zones shift to MDT and PDT respectively, maintaining the same 1-hour gap. The exception is Arizona, which stays on MST (UTC−7) year-round, making it 2 hours ahead of California during summer.

What is the time difference between Los Angeles and Denver?

Los Angeles (Pacific Time) is 1 hour behind Denver (Mountain Time) during standard time and also 1 hour behind during daylight saving time, since both cities observe DST on the same schedule. The 1-hour gap is stable throughout the year for these two cities specifically.

What is the time difference between Los Angeles and Phoenix?

Los Angeles and Phoenix are in the same time zone (Pacific and Mountain Standard Time respectively) during winter months — both at UTC−7/−8 producing a 1-hour gap. But during summer, California moves to PDT (UTC−7) while Arizona stays at MST (UTC−7), creating a 0-hour difference. This anomaly catches many travelers off guard.

PST vs MST: Time Difference and Conversion

January 31, 2026

Pacific Standard Time (PST, UTC−8) and Mountain Standard Time (MST, UTC−7) are adjacent US time zones separated by just 1 hour. Despite the small gap, the PST/MST boundary matters for anyone coordinating between the US West Coast and inland states like Colorado, Utah, and New Mexico — and especially for anyone dealing with Arizona’s unique DST opt-out.

The 1-Hour Gap

MST is UTC−7 and PST is UTC−8, making Mountain time 1 hour ahead of Pacific time. When San Diego is at 8 AM PST, Salt Lake City is at 9 AM MST. The gap is small enough that most scheduling conflicts are easily managed, but large enough to cause missed calls if overlooked in calendar settings.

During summer, both zones observe daylight saving time simultaneously. PST becomes PDT (UTC−7) and MST becomes MDT (UTC−6). The 1-hour gap persists unchanged. The transition happens on the second Sunday in March (spring forward) and the first Sunday in November (fall back) for both zones.

Compare Pacific and Mountain time

Add Los Angeles and Denver to see both current times and verify the 1-hour gap at a glance.

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Quick Conversion Reference

To convert PST to MST, add 1 hour. To convert MST to PST, subtract 1 hour.

Pacific Time (PST/PDT)	Mountain Time (MST/MDT)
6:00 AM	7:00 AM
7:00 AM	8:00 AM
8:00 AM	9:00 AM
9:00 AM	10:00 AM
11:00 AM	12:00 PM (noon)
12:00 PM (noon)	1:00 PM
2:00 PM	3:00 PM
4:00 PM	5:00 PM
5:00 PM	6:00 PM

Tip

Because the gap is only 1 hour, almost any meeting time that works for one zone works for the other. Standard business hours (9 AM–5 PM) in both zones overlap almost completely, leaving only early morning and late afternoon as points of friction.

The Arizona Exception

Arizona does not observe daylight saving time, remaining on Mountain Standard Time (UTC−7) year-round. This creates a notable seasonal shift in its relationship to California. During winter (standard time), Los Angeles (PST, UTC−8) is 1 hour behind Phoenix (MST, UTC−7) — a normal PST/MST gap. But in summer, California switches to PDT (UTC−7) while Arizona stays at MST (UTC−7). Both cities are now at the same UTC offset, meaning Los Angeles and Phoenix show the same time.

Example

A tech company with offices in San Francisco and Phoenix schedules a recurring 5 PM PST team sync. In January (winter), Phoenix joins at 6 PM MST — slightly late but acceptable. In July (summer), both cities are at UTC−7, so the meeting is now at 5 PM for both. No adjustment needed for summer, but remember to update calendar invites when the clocks change in November.

The Navajo Nation Complication

The Navajo Nation reservation, which spans parts of Arizona, Utah, and New Mexico, does observe daylight saving time even though the surrounding Arizona land does not. The Hopi Reservation, located entirely within the Navajo Nation in Arizona, follows Arizona’s non-DST policy. This creates a geographic oddity where driving through northeastern Arizona can put you in and out of different time conventions within miles.

For practical scheduling purposes, confirm with specific Arizona counterparts whether they follow standard Arizona (no DST) or Navajo Nation (DST) time when arranging meetings during summer months.

Schedule across Mountain and Pacific zones

Use the meeting planner to find optimal times for teams spanning the West Coast and inland US.

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Time Zone ConverterConvert times between Pacific and Mountain zones, with Arizona’s DST exception handled automatically.

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Frequently Asked Questions

How many hours ahead is MST compared to PST?: Mountain Standard Time is 1 hour ahead of Pacific Standard Time during winter. In summer both zones shift to MDT and PDT respectively, maintaining the same 1-hour gap. The exception is Arizona, which stays on MST (UTC−7) year-round, making it 2 hours ahead of California during summer.
What is the time difference between Los Angeles and Denver?: Los Angeles (Pacific Time) is 1 hour behind Denver (Mountain Time) during standard time and also 1 hour behind during daylight saving time, since both cities observe DST on the same schedule. The 1-hour gap is stable throughout the year for these two cities specifically.
What is the time difference between Los Angeles and Phoenix?: Los Angeles and Phoenix are in the same time zone (Pacific and Mountain Standard Time respectively) during winter months — both at UTC−7/−8 producing a 1-hour gap. But during summer, California moves to PDT (UTC−7) while Arizona stays at MST (UTC−7), creating a 0-hour difference. This anomaly catches many travelers off guard.