A Bruneian postcode has six characters, consisting of two uppercase letters and immediately followed by four digits. Examples of postcodes are "BB3713" which represents the postcode areaAnggerek Desa; "KB4533" which represents Panaga; and "BA2110" which represents Jabatan Hal Ehwal Masjid or the Department of Mosque Affairs.
The second letter denotes the mukim code, corresponding directly to the mukims or subdistricts of Brunei, the country's second-level administrative divisions.
Villages
The first two digits after the two letters representthe village code. Usually, it corresponds directly to the villages, the country's third- and lowest-level administrative divisions. However, a few villages may have more than one postcode areas. Some postcode areas may also represent defunct villages or villages which have been subsumed under other nearby villages.
Post offices
The last two digits represent the post office code, which generally correspond to the post office of, or nearest to, the village or mukim. A few may also correspond to the function of the place, and this exclusively refers to government ministries or departments. They have postcodes with the last digit "0".
Postcodes
A complete postcode represents either an area or a government agency.
Area postcode
An area postcode is usually equivalent to the village subdivision – the postcode "TB1741" corresponds directly the whole area which constitutes Sinaut, a village in Tutong District. However, a few postcodes may represent specific parts of a village. For example, although the postcode for Rataie, a village in Temburong District, is "PE2751", the areas in it which constitute the Rancangan Perpindahan Negara- and Skim Tanah Kurnia Rakyat Jati-type public housing have separate postcodes of "PE2951" and "PE3151" respectively. Some postcodes may also represent defunct villages and villages which have been subsumed other nearby villages. Bangar, the town of Temburong District, is also a village subdivision. However, it has two postcodes: "PA1151" and "PE1351", which constitute the postcode areas "Pekan Bangar Lama" and "Pekan Bangar" respectively. This means that the Bangar area once had two separate village subdivisions but have since been combined into the current Bangar subdivision. A few postcodes may represent areas that are officially village subdivisions but are not sufficiently functioning as such. For example, "BB2513" represents the Old Airport Area, mainly an administrative area where many government departments are located.
Government postcode
A few postcodes are exclusively for government agencies instead of areas. All postcodes with the last digit "0" constitute government ministries or departments. However, not all of them have dedicated postcodes, that is having "0" as their last digit – some still use the postcodes of the areas where they are located. For example, Jabatan Laut uses the postcode "BT1728", which is also the postcode for Serasa, the village where the department is located.
