International phone numbers: reading country codes
How to tell where an international number is from, why some area codes look domestic, and the 'one-ring' scam.
Country codes
International numbers start with + and a country calling code of one to three digits — +44 for the United Kingdom, +91 for India, +52 for Mexico.
Caribbean look-alikes
Many Caribbean countries use +1 with their own area codes (for example 876 for Jamaica and 809 for the Dominican Republic). They look like U.S. numbers but are billed as international.
The 'one-ring' scam
Scammers call once from an international premium-rate number hoping you'll call back and pay high per-minute charges. If you don't recognize an international number, don't call back.