International dialling codes are +590 for Saint Martin and +1-721 for Sint Maarten.

Calling from Saint-Martinst martin island information• To call Saint-Martin : 10-digit number
• To call Sint-Maarten
- Landline : 00 1 721 54 + 5-digit landline number
- Mobile : 00 1 721 55 + 5-digit mobile number
• To call USA : 001 + state code + number
• To call mainland France : 10-digit number

From Sint-Maarten
• To call Saint-Martin :
- Landline : 00 59 + 10-digit landline number
- Mobile : 00 59 + 10-digit mobile number
• To call Sint-Maarten : 7-digit number
• To call USA : 001 + state code + number
• To call mainland France : 00 33 + 10-digit number