米国
Country code
International prefix
The United States uses country code +1 under the North American Numbering Plan (NANP), shared with Canada and several Caribbean nations. With 331 million people and the world's largest economy, a US local number is essential for any global business.
国
米国
2 Digit ISO
私たち
Country Calling Code
+1
ISO Alpha-3
USU
Capital
LiveWashington D.C.
--:--:-- --
Time Zone
Eastern / Central / Mountain / Pacific
Quick Facts
How to call 米国 from abroad
International dialing is a four-step process.
Use + on mobile to skip the exit code entirely.
Exit code
Dial from US/Canada (or use +)
Country code
United States international prefix
Area / city code
Local routing prefix
Local number
Subscriber number
International format
Shorthand (works from any device): +1 212 555 1234
Benefits of calling 米国
with letsdial
Get a local +1 number
A US +1 caller ID with a recognisable area code (212 New York, 310 Los Angeles) signals a local presence and dramatically improves answer rates from American contacts.
United States and 50+ countries, one plan
Cover the US and 50+ global markets from one letsdial subscription — no per-state or per-city add-ons for any of the 50 states.
Full call analytics
Track every US call across ET, CT, MT, and PT time zones — answer rates, peak hours, and team performance all in one dashboard.
Works on any device
Mobile app, desktop, or IP phone — your +1 number works anywhere your team operates, from New York to California.
One platform. Every call, message and team — connected.
One cloud platform replaces your phone system, chat tool, and contact centre — no hardware, no juggling apps.
Reach 米国 and 50+ countries from one dashboard.
50+
Countries covered
99.9%
Uptime SLA
2 min
Setup time
0
Hardware needed
Voice & Video Calls
Crystal-clear HD calls to United States and 50+ countries from one number.
Team Messaging
Chat, share files, and collaborate — all inside the same platform you call from.
Real-Time Analytics
Live dashboards for call volumes, answer rates, and agent performance.
Global Number Coverage
Local +1 numbers plus 50+ country codes — managed from one dashboard.
米国 & neighbouring countries
US numbers follow the North American Numbering Plan: +1 + 3-digit area code + 7-digit local number, always totalling 11 digits in international format. There is no trunk prefix to drop.
Tips for calling 米国
4 things to check before you dial internationally
US numbers follow NXX-NXX-XXXX
All US numbers are 10 digits: 3-digit area code + 3-digit exchange + 4-digit subscriber number. From abroad, dial +1 + all 10 digits. The US uses no trunk prefix — never add a leading 0.
Text before you call
SMS is the dominant pre-call channel in the US — a brief text identifying yourself before calling significantly improves answer rates compared to a cold call from an unknown number.
Show a local US area code
US recipients are far more likely to answer calls from a familiar local area code. A letsdial US virtual number with the right area code (212 NY, 213 LA, 312 Chicago) dramatically lifts pickup rates.
The US spans 4 main time zones
The contiguous US spans ET (UTC-5), CT (UTC-6), MT (UTC-7), and PT (UTC-8). Always confirm your contact's state before scheduling — 9 AM ET means only 6 AM for a California contact.
米国 communication insights
93%
Internet penetration
90% of the US population uses the internet, one of the highest rates globally.
97%
Mobile users
97% of Americans use mobile phones, with voice and data services widely accessible nationwide.
81%
Smartphone owners
81% of US adults own a smartphone, making mobile-first communication the business standard.
95%
Digital businesses
95% of US businesses have adopted digital tools for internal and external communication.
List of 国コード
50+ countries listed with their international dial prefix and ISO code.
Filter by letter or search to find any country code instantly.
Frequently asked about 米国
US numbers follow the format +1 (area code) (7-digit local number), with no trunk prefix needed. Simply dial +1 followed by the 10-digit number, for example +1-212-555-0100 for a New York City number. letsdial handles the international routing automatically when you enter the full E.164 format.
Get a local 米国 number in minutes.
Build trust with 米国 customers using a local +1 virtual phone number — from the same letsdial dashboard your whole team already uses.
Looking up US area codes? Browse all US area codes →