Beijing Time

The time in China follows a single standard time offset of UTC+08:00 (eight hours ahead of Coordinated Universal Time), despite China spanning five geographical time zones. The official national standard time is called Beijing Time (Chinese: 北京时间) domestically and China Standard Time (CST) internationally. Daylight saving time has not been observed since 1991.

The special administrative regions (SARs) maintain their own time authorities, with standards called Hong Kong Time (香港時間) and Macau Standard Time (澳門標準時間). These have been equivalent to Beijing time since 1992.

In addition, a second time standard is used in Xinjiang, two hours less than the Beijing Time (UTC+06:00), which is called Ürümqi Time (乌鲁木齐时间) or Xinjiang Time (新疆时间).

In the 1870s, the Shanghai Xujiahui Observatory was constructed by French catholic missionary. In 1880s officials in Shanghai French Concession started to provide time announcement service using the Shanghai Mean Solar Time provided by the aforementioned observatory for ships into and out of Shanghai. By the end of 19th century, the time standard provided by the observatory have been switched to GMT+8. The partice have been further spread to other coastal port, and in 1902 the "Coastal Time" is proposed to be the universal timezone for all the coastal port in the China. However, the timezone for rest of the China remain undetermined.

Until year 1913, the official time standard for the entire China was still the apparent solar time of Beijing, the capital of the country at the time. Starting from year 1914, the Republic of China government began adopting the Beijing Local Mean Solar Time as the official time standard. In 1918, five standard time zones have been proposed by the Central Observatory of Beiyang government of Republic of China, including the Kunlun (UTC+05:30), Sinkiang-Tibet (UTC+06:00), Kansu-Szechwan (UTC+07:00), Chungyuan (UTC+08:00), and Changpai (UTC+08:30).

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