Telephone numbers in Curaçao and the Caribbean Netherlands
Country Code: +5999
International Call Prefix: 00
The country code +5999 was assigned to the Netherlands Antilles, and is now in use by Curaçao and the Caribbean Netherlands.
Aruba and Sint Maarten, also former parts of the Netherlands Antilles, discontinued using the code in 1986 and 2011 respectively. Aruba now uses country code +297, and Sint Maarten uses the North American Numbering Plan country code +1 with area code 721.
Area codes
Originally each island had an area code each with the length of the local numbering varying from island to island, however beginning in 1999, the numbers were modified so that each local number was seven digits long. This change left the islands without any area codes, except for Curaçao, which has the area code of 9 along with the seven digit local number.Sint Maarten joins NANP
On 2 October 2009, the North American Numbering Plan Administration announced that it had approved the request of Sint Maarten's government to join the NANP and had assigned the territory area code 721. Effective 30 September 2011, Sint Maarten's country code changed to the NANP standard of +1. A permissive dialing period of one full year was in place when both area code 721 and +5999 could be used. Use of +1-721 is now mandatory; a recorded message reminding callers to the +599 numbers to use +1-721 remained active until 30 September 2013.Historic list of area codes and number ranges
| Island | Number range |
| Bonaire | 7xx xxxx 717 xxxx 750 xxxx 700 xxxx 701 xxxx 795 xxxx 796 5hhh |
| Curaçao | 4xx xxxx 5xx xxxx 6xx xxxx 7xx xxxx 8xx xxxx |
| Sint Maarten | 5xx xxxx |
| Saba | 4xx xxxx |
| Sint Eustatius | 3xx xxxx |
| Aruba | 8xx xxxx |
| Non-geographic | 1xx xxxx 6xx xxxx |