The system is organised around the six administrative districts for local government on the island, with each district allocated a numerical range. Most of the four digit numbers are allocated to small geographic areas, such as streets, urban communes or villages, although some are reserved for government use.

Due to the division of Cyprus, only the (internationally-recognised) Republic of Cyprus uses this post code system. Mail sent to the de facto state of Northern Cyprus must instead be addressed to via Mersin 10, TURKEY via Mersin in southern Turkey. However, five-digit postcodes were introduced in northern Cyprus in 2013,^[1] in a similar format to those of Turkey, with the first two digits being 99, and the last three indicating the locality.

The two British Sovereign Base Areas (or SBAs) of Akrotiri and Dhekelia are not part of the Republic of Cyprus, although the Cypriot villages within these areas use the Cyprus post code system. British military organisations and personnel use British Forces Post Office numbers, BFPO 57 for Akrotiri and BFPO 58 for Dhekelia.