EuroBillTracker

My google search returned this

NETHERLANDS ANTILLES: Write the street address and town (if any) above the name of the island:

US Consulate General
J.B. Gorsiraweg 1 (street and number)
Willemstad (town)
CURAÇAO (island)
NETHERLANDS ANTILLES

It looks like they don´t use postal code, just the town and Island..

pastel wrote:It looks like they don´t use postal code, just the town and Island..

The voice of authority (when it comes to such codes) agrees with you.
http://www.upu.int/post_code/en/countries/ANT.pdf

Christian