Compare PST vs MST
See the 1-hour difference between Pacific Standard Time and Mountain Standard Time, check DST changes, and find the best meeting times.
How to Find the Time Difference Between PST and MST
Open the PST vs MST converter: Go to https://www.xconvert.com/time-converter/pst-vs-mst to load a comparison grid with PST and MST already shown as separate rows. This view is useful when you are scheduling a support handoff between a California team working on Pacific Time and an Arizona, Colorado, or Utah contact using Mountain Time, because you can see both day timelines side by side instead of calculating the offset manually.
Add cities that matter to your schedule: Click + Add City and add specific locations such as Los Angeles, Phoenix, and Denver to compare how Pacific and Mountain schedules line up in real business centers. This is especially helpful for software teams, logistics coordinators, and sales staff who work across the U.S. West, because Phoenix often behaves differently from Denver during daylight saving periods even though both are commonly associated with the Mountain region.
Drag to select the meeting window: Click Select to enter selection mode, then drag across the colored timeline on the PST row to highlight a working block such as 9:00 AM to 11:00 AM PST. That selection shows immediately as 10:00 AM to 12:00 PM MST, confirming the standard one-hour difference and making it easy to see whether a West Coast morning call still lands inside normal green work-hour blocks for Mountain-based colleagues.
Export and share the chosen time: After selecting the range, use the export options shown on the page: ICS download, Google Calendar, Gmail, Copy to clipboard, or Share link. For example, if you are booking a recurring vendor call between Seattle and Denver, the ICS file can be sent to participants so their calendar apps display the event in local time automatically, while the share link is useful for quickly confirming the slot in Slack or email.
PST vs MST Offset Explained
PST is 1 hour behind MST. In pure standard-time terms, Pacific Standard Time (PST) is UTC-8 and Mountain Standard Time (MST) is UTC-7. That means when it is 9:00 AM PST, it is 10:00 AM MST, and when it is 5:00 PM PST, it is 6:00 PM MST.
The seasonal complication is that many places do not stay on PST or MST all year. Most Pacific locations such as Los Angeles, San Francisco, Seattle, and Las Vegas switch to Pacific Daylight Time (PDT, UTC-7) in spring and summer, while many Mountain locations such as Denver, Salt Lake City, Albuquerque, and Calgary switch to Mountain Daylight Time (MDT, UTC-6). In the United States and Canada, daylight saving time in 2025 begins on March 9, 2025, and ends on November 2, 2025.
When both regions observe daylight saving time, the practical difference usually remains 1 hour: PDT is UTC-7 and MDT is UTC-6. So during summer, 9:00 AM in Los Angeles is still 10:00 AM in Denver. This is why many users experience the PST-vs-MST gap as consistently one hour for most mainstream U.S. business scheduling.
The biggest exception is Arizona, especially Phoenix, because most of the state does not observe daylight saving time and stays on MST (UTC-7) year-round. This creates a seasonal split: during winter, PST (UTC-8) is 1 hour behind Phoenix; during summer, PDT (UTC-7) is the same time as Phoenix. For example, in January, 9:00 AM in Los Angeles equals 10:00 AM in Phoenix, but in July, 9:00 AM in Los Angeles equals 9:00 AM in Phoenix.
This matters for real operations. U.S. companies with offices in California and Arizona, remote engineering teams spread between Seattle and Denver, and transportation planners coordinating freight through Nevada, Utah, and Colorado often assume Mountain Time is always one hour ahead of Pacific Time, but that is only reliably true when comparing regions that follow the same DST pattern. If your meeting involves Phoenix, you should always check the specific date on the converter before sending invites.
For business context, Pacific Time covers major economic hubs including Los Angeles metro area (about 12.8 million people), San Francisco Bay Area (about 7.7 million), and Seattle metro (about 4.0 million), where technology, media, entertainment, and venture-backed startups are heavily concentrated. Mountain Time includes major centers such as Denver metro (about 3.0 million) and Phoenix metro (about 5.0 million, though Phoenix stays on MST year-round), making this comparison common for SaaS sales calls, real estate coordination, airline operations, and regional customer support coverage.
Frequently Asked Questions
What is the exact time difference between PST and MST?
The standard offset is 1 hour, with PST at UTC-8 and MST at UTC-7. In practical terms, Mountain Standard Time is ahead, so if it is 8:00 AM PST, it is 9:00 AM MST. This is the baseline comparison people use for winter scheduling and for locations that remain on standard time.
Is MST always one hour ahead of PST?
No, not in every real-world case, because daylight saving rules affect how the labels are used across the year. If you are comparing true PST to true MST, the difference is always one hour, but many cities switch to PDT or MDT seasonally, and Phoenix stays on MST year-round. That means a California-to-Phoenix comparison is one hour apart in winter but the same clock time in summer.
How does daylight saving time affect PST vs MST?
During the daylight saving season, many Pacific locations move from PST (UTC-8) to PDT (UTC-7), and many Mountain locations move from MST (UTC-7) to MDT (UTC-6). In 2025, the transition starts on March 9 and ends on November 2 in most of the U.S. and Canada. If both places observe DST, the visible gap usually remains one hour, but if one location does not change clocks, the difference can temporarily change.
Why is Phoenix different from Denver when comparing Pacific and Mountain time?
Phoenix, Arizona stays on MST (UTC-7) for most of the year and does not observe daylight saving time, while Denver, Colorado changes between MST (UTC-7) in winter and MDT (UTC-6) in summer. As a result, Los Angeles and Denver are typically one hour apart year-round, but Los Angeles and Phoenix are one hour apart in winter and aligned in summer. This difference is important for travel bookings, customer support shifts, and recurring meetings involving Arizona-based teams.
When it is 9 AM PST, what time is it in MST?
If you are comparing strict standard time labels, 9:00 AM PST equals 10:00 AM MST. That is the simplest conversion and is commonly used for winter schedules, internal operations documents, and time-zone training references. However, if the Pacific location is actually on PDT in summer and the Mountain location is Phoenix on MST, then 9:00 AM Pacific may equal 9:00 AM in Phoenix on that date.
What are the best meeting hours between Pacific and Mountain time zones?
Because the difference is usually only one hour, there is a large overlap in standard workdays. A meeting scheduled for 9:00 AM to 12:00 PM Pacific appears as 10:00 AM to 1:00 PM Mountain, which fits normal office hours for remote teams in California, Nevada, Colorado, and Utah. This makes PST/MST coordination easier than East-West U.S. scheduling, especially for product demos, recruiting interviews, and operations check-ins.
How do I schedule a recurring call between California and Arizona correctly?
Use the converter with the exact meeting date selected, because Arizona does not follow the same seasonal clock changes as California. For example, a call that is 10:00 AM Los Angeles time in January appears as 11:00 AM in Phoenix, but the same 10:00 AM Los Angeles call in July appears as 10:00 AM in Phoenix. For recurring meetings across spring and fall, exporting a calendar event after checking the date helps prevent one-hour mistakes.