Ideal
Morning
local
EST (UTC−5)
PST (UTC−8)
+1-671 · UTC+10
Best Time to Call
Guam
from the United States
Guam shares the +1 code with the US mainland, using its own dedicated 671 area code. From the US East Coast, business hours in Guam fall between 6:00 PM and 2:00 AM EST.
Best EST: 6:00 PM – 2:00 AM (+1 day)
Mon–Fri
United States
04:15 PM
Business hours
14h
difference
Guam
06:15 AM
Sleeping
// Best Time to Call
When to Call Guam
A 9-to-5 day in Hagåtña never overlaps one in New York — at 9:00 AM ET it is 12:00 AM there — so reach them 6:00 PM–2:00 AM ET or leave a message.
Ideal
Afternoon
local
EST (UTC−5)
PST (UTC−8)
Avoid
Avoid
local
EST (UTC−5)
PST (UTC−8)
| Local Time | UTC | EST / New York | CST / Chicago | PST / LA |
|---|---|---|---|---|
| Open | ||||
| Noon | ||||
| PM | ||||
| Close |
US columns use standard time (EST/CST/PST); between the second Sunday in March and the first Sunday in November, US clocks are one hour later.
// Calling Guide
How to call Guam — the short version.
Dialing steps
- 1Dial your exit code — 011 from the US and Canada, 00 from most of Europe.
- 2Add the Guam country code: +1-671.
- 3Enter the national number. If it's written with a domestic trunk prefix (often a leading 0), that prefix is usually dropped after the country code.
Best time to call
- 9:00 AM – 5:00 PM in Hagåtña is 6:00 PM – 2:00 AM EST.
- A 9-to-5 day in Hagåtña never overlaps one in New York — at 9:00 AM ET it is 12:00 AM there — so reach them 6:00 PM–2:00 AM ET or leave a message.
Quick tips
- Working days: Mon–Fri.
// Calling Etiquette
Calling etiquette in Guam
Calling culture
Business culture in Guam blends US and Pacific Islander traditions — a warm, relationship-oriented approach is typical.
Working week
Mon–Fri.
Free tools
Look up a number from Guam
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Frequently Asked
Calling Guam — Common Questions
Everything you need to know about reaching contacts in Guam.
Calls outside local business hours in Guam are less likely to be answered live, but Rozper's AI receptionist and voicemail-to-text still capture the call and notify your team immediately — so you're not limited to the 6:00 PM–2:00 AM EST overlap.
A recognizable 671 area code helps build trust with local consumers, distinguishing genuine local presence from generic +1 callers.
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