Oceania · Micronesia · Dependency
Current time in Guam
A single time zone at UTC+10:00.
Saturday, June 6, 2026
About Guam's time
A single time zone.
Guam uses a single time zone—Chamorro Standard Time (ChST) at UTC+10:00 year-round, with no daylight saving time. As a U.S. territory in the western Pacific, its time zone reflects its close ties to the broader Micronesian and East Asian economic sphere.
Major cities
Cities of Guam.
History
How Guam keeps time.
Guam adopted Chamorro Standard Time (UTC+10:00) as its official time in 2000, replacing the previous system that had used both UTC+10:00 and UTC-10:00 due to confusion from its proximity to the International Date Line.
Prior to 2000, parts of Guam effectively experienced two different local times because of the date line running near the island. The 2000 reform unified the island under a single time zone to reduce confusion for residents, businesses, and the U.S. military presence on the island. This standardized Guam’s time for the first time in modern history.
Did you know?
Things about Guam's time.
Guam’s location just west of the International Date Line creates an interesting quirk: while it shares the same calendar day as Australia and New Zealand, it is over 14 hours ahead of U.S. Eastern Time—making real-time communication with the U.S. mainland challenging.
Despite being a U.S. territory, Guam’s time zone aligns more closely with neighboring Micronesian islands and parts of Russia than with any continental U.S. state. This reflects its geographic reality rather than political boundaries.
Chamorro Standard Time (ChST) has no daylight saving adjustments, which simplifies scheduling but can create stark seasonal differences in sunrise and sunset times—sunrise can be as early as 5:30 AM inJune and as late as 6:30 AM in December.
Frequently asked questions
Common questions about Guam's time zone, daylight saving rules, and how to handle it in software. Can't find what you need? Email [email protected].
- What is the time difference between Guam and Washington, D.C.?
- Guam is 14 hours ahead of Washington, D.C. (UTC-5), so when it's 8 AM in D.C., it's 10 PM the previous day in Guam.
- Is there daylight saving time in Guam?
- No, Guam does not observe daylight saving time. Chamorro Standard Time (ChST) is UTC+10:00 year-round.
- Can I call my family in Guam during U.S. business hours?
- It’s generally not advisable. A 9 AM call from New York would be 11 PM in Guam the previous day. Early morning or late evening calls from the U.S. mainland are better to catch Guam residents during their waking hours.
- Why doesn’t Guam follow U.S. time zones?
- Guam is geographically located in the western Pacific, far from the continental U.S. Its time zone reflects its position near the International Date Line and regional alignment with Micronesia, not U.S. domestic time zone logic.
- Does Guam ever change its clocks?
- No, there are no clock changes in Guam. The island stays on Chamorro Standard Time (UTC+10:00) all year.
- How does Guam’s time compare to nearby islands?
- Guam shares Chamorro Standard Time (UTC+10:00) with the Northern Mariana Islands. Nearby Federated States of Micronesia use UTC+11:00 or UTC+10:00 depending on location, while Palau uses UTC+9:00.
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