In 1908, during the Dutch East Indies colonial era, only Java and the Madura Island were initially given time until 1932, when the government utilised UTC+06:30 up to +09:30.

The Dutch reoccupied the country following its 1945 independence with UTC+06:00 up to +09:00 established, but it was reverted to the 1932 system after they recognised Indonesia's sovereignty.

Without any significant season changes, the daylight saving time system is not observed anywhere in Indonesia, as is other Southeast Asian countries.

412, divided the entire colony into six time zones separated by 30 minutes as follows: During the Japanese occupation of the Dutch East Indies, from 27 March 1942 to 24 September 1945, both western and central parts of Indonesia used Japan Standard Time (JST) (UTC+09:00) for the sake of the effectiveness of Japanese military operations in Indonesia.

Following Dutch recognition of Indonesian sovereignty, a presidential regulation came into effect on 1 May 1950 once again dividing the country into six time zones separated by half an hour.

[1][2] On 12 March 2012, Coordinating Minister for the Economy Hatta Rajasa said: "According to research, with a single time zone the country could cut costs by trillions of rupiah.