Date of Issue : 1 Jul 1979
Postmark : Singapore
Denomination : 10c and 50c
Stamp Size : 39 mm x 24.5 mm
Paper : Unwatermarked
Printing Process : Offset Lithography
Prior to the introduction of the 4-digit postal code on 1 Jul 1979, the 2-digit Postal District Number System was in use in Singapore. Introduced in 1950, it was to facilitate the sorting of mail to the delivery post offices in the country. With the increase in the number of postal articles delivered each day, the old system has become inadequate, hence warranting the need to have a new postal code system to assist postal sorters to distribute mail with speed and accuracy. The 4-digit postal code is derived by adding two more digits to the existing 2-digit Postal District Number. This set of stamps was released to mark the introduction of the 4-digit Postal Code System in Singapore.