Calling to Guam
- A leading ‘1’ is included in the international call sequence.
- A leading '+' in the phone number means 'dial your country's exit code'.
- Calling from a mobile phone: dial from on the country where you're currently located.
- Calling from a VoIP or satellite phone: dial from on the country where the phone is registered.
… to a mobile (cellular) phone or text (sms)
Use the same call sequence.
When calling a mobile phone user, dial to the country where the mobile phone is registered, regardless of where the person is roaming.
… to a VoIP phone
Use the same call sequence.
When calling a VoIP phone user, dial to the country where the VoIP phone is registered, regardless of where the person is roaming.
… to a satellite phone
Guam does not have a country-specific satellite phone system.
Most satellite phones operate on their country code – calls to these satellite phones follow their call sequence.
… sending a fax
Use the same call sequence.
Calling within Guam (domestic dialing)
There is no trunk prefix (1) or area code (671) used when calling within Guam.
Only the seven-digit phone number is dialed.
seven digits |
local phone number |
Guamanian phone numbers explained
Number details
Guam’s phone numbers are ten digits (eleven including a leading ‘1’ that acts as a country code for the entire NANP calling region).
The first three digits are ‘671’ – an area (geographic) code to designate Guam within the North American Numbering Plan.
The first three digits of the local phone number are an exchange within Guam’s code of ‘671’.
Mobile numbers are intermixed with land-line phone numbers.
An example of a Guamanian number
The War in the Pacific National Historic Park lists its phone number in Guam as (671) 333-4050.
Number explanation
1 | 671 | 333 4050 |
country code for Guam | area code for Guam within the NANP | local phone number in Guam |
Local example – calling from another location in Guam
Dial the seven-digit phone number when calling anywhere within Guam. Do not include the trunk prefix/country code ‘1’ or the area code ‘671’ in domestic calls.
333 4050 |
local phone number in Guam |
International example – calling from the United States, Canada, or another country of the NANP (most of the Caribbean and U.S. territories in the Pacific)
To call within the NANP dial the phone call with the same call sequence as a U.S. or Canadian long distance call.
Dial the combined country code/trunk prefix of ‘1’, then Guam’s area code within the NANP of ‘671’, then the local seven-digit phone number.
1 | 671 | 333 4050 |
long distance trunk prefix | area (geographic) code for Guam | local phone number in Guam |
International example – calling from a country outside of the NANP (the United States, Canada, most of the Caribbean, and U.S. Territories in the Pacific)
To call from a country from outside the NANP, dial the exit code of the country you’re calling from, then the NANP country code/trunk prefix of ‘1’, then Guam’s area code of ‘671’, then the local phone number.
exit code | 1 | 671 | 333 4050 |
exit code of the country the call is dialed from | country code for the North American Numbering Plan | area (geographic) code for Guam | local phone number in Guam |
Calling from Guam
… to another country in the North American Numbering Plan (NANP)
NANP countries include Canada, the United States (and associated territories), and most regions of the Caribbean.
Dial the phone call starting with the trunk prefix/country code of ‘1’, then the area code and local phone number.
… to all other regions of the world
‘011’ is used as an exit code when dialing an international phone call from Guam to a location outside the NANP calling region (the United States, Canada, most regions of the Caribbean, and U.S. Territories in the Pacific).
Sources and more resources
- National NANPA – The North American Numbering Plan Administration. Telecommunications numbering system regulator for numbering administration across the North American Numbering Plan.
- ITU (International Telecommunications Union) – United Nations specialized agency for information and communications technologies.
- International Telecommunications Union – DIALLING PROCEDURES (INTERNATIONAL PREFIX, NATIONAL (TRUNK) PREFIX AND NATIONAL (SIGNIFICANT) NUMBER) (IN ACCORDANCE WITH ITU-T RECOMMENDATION E.164 (11/2010)) – A collection of dialing procedures for all countries and regions of the world. Retrieved 16 September 2016.
- International Telecommunications Union – Guam (country code +1 671) National National Numbering Plan – Details of Grenada’s telephone numbering plan as submitted to the ITU. Retrieved 28 November 2016.
- Wikipedia – Telephone numbers in Guam (country code +1 671) – Wikipedia entry for telephone number data for Guam’s calling plan within the North American Numbing Plan. Includes specific number ranges for each city as well as detail on calling procedures.
- BT – The Phonebook – Guam – Entry for Grenada in the British Telecom international directory.