CST — Central, China or Cuba Standard Time
CST is ambiguous: it stands for 3 different times, all in use today. When a message says “CST”, the sender’s country usually tells you which one is meant; to be safe, write the UTC offset (for example CST = UTC−6, CST = UTC+8 or CST = UTC−5).
- Central Standard Time · UTC−6 · North America
- China Standard Time · UTC+8 · China
- Cuba Standard Time · UTC−5 · Cuba
Central Standard Time
CST stands for Central Standard Time, UTC−6, 6 hours behind UTC. It is used in North America: in winter in the United States and Canada, and all year in Mexico (Mexico City), Canada (Regina) and Guatemala.
Countries and territories: United States, Canada, Mexico and Guatemala.
Zones: America/Chicago, America/Winnipeg, America/Mexico_City, America/Regina, America/Guatemala.
China Standard Time
CST stands for China Standard Time, UTC+8, 8 hours ahead of UTC. It is used all year in China.
Countries and territories: China, Macau and Taiwan.
Zones: Asia/Shanghai, Asia/Macau, Asia/Taipei.
Cuba Standard Time
CST stands for Cuba Standard Time, UTC−5, 5 hours behind UTC. It is used in winter in Cuba; from the second Sunday in March at 00:00 to the first Sunday in November at 01:00, the same places switch to CDT (UTC−4).
Countries and territories: Cuba.
Zones: America/Havana.