Postal codes in Singapore
Postal codes in Singapore have consisted of six digits since 1995, replacing the four-digit system introduced in 1979. They are administered by Singapore Post. 6-digit postal code. The 6-digit postal code is made up of the sector code and the delivery point. The sector is represented by the first two numbers of the postal code. The remaining four numbers define the delivery point within the sector. e.g. 56 is the sector code; 9933 is the delivery point, i.e. house or building. For Housing and Development Board (HDB) residential blocks, the block number is  included in the postal code. e.g. HDB residential blocks with the same number in the same postal sector are differentiated by their postal codes as follows: Similarly, for a HDB residential block sharing the same number as another block in the same postal sector, but have an added suffix behind are differentiated by their postal codes as follows: The postal codes for private residential, commercial and industrial houses and buildings are assigned based on the alphabetical sequence of the street names in each sector. This means that the codes for a particular postal sector have been assigned first to houses  and buildings located along street names beginning with 'A', followed by 'B' and so on. The postal codes for such properties do not contain the corresponding house or building numbers included in the postal code. HDB industrial and commercial blocks also use this system. Postal districts. This table lists the postal districts: History. Singapore was originally divided into 28 postal districts on 6 March 1950, with a number being allocated to each district. For example, the Orchard Road area was in District 9. This was superseded by a new four-digit system on 1 July 1979, with the last two  digits representing a sector in each district. There were in total 81 sectors. On 1 September 1995, this was replaced by a six-digit system, in which every building was given its unique postcode, the first two digits of which represented the old sector, i.e. 23. Although the old districts are no longer used by Singapore Post, they are still widely used to refer to locations of properties for sale or rent. Addressing from overseas. SingPost recommends the following format for addresses: Generally, the last line "SINGAPORE" is omitted when posting within the country.