CST time now (Central Standard Time)

What CST means

CST stands for Central Standard Time, UTC−6. It is used in the central United States, central Canada and most of Mexico and Central America.

It is a standard (winter) time. Places on CST that observe daylight saving time switch to CDT (UTC−5) in summer, so CST is a fixed offset while the local clock is not.

CST is ambiguous. It also means China Standard Time (UTC+8, China, Taiwan and Macau) and Cuba Standard Time (UTC−5, Cuba). This page shows UTC−6, the meaning English searchers usually want.

Three different CSTs

CST is one of the most ambiguous abbreviations in use. In North America it is Central Standard Time, UTC−6: Chicago, Dallas, Mexico City and Winnipeg’s old zone. In China it is China Standard Time, UTC+8, used by the whole country (and by Taiwan and Macau under the same letters). Cuba writes CST for Cuba Standard Time, UTC−5. The same three letters cover a 14-hour spread.

Our search data shows that people who type “CST” on an English search engine overwhelmingly mean US Central time, so this page shows UTC−6 first. When you read CST in a message from Asia, check: “CST 9:00” from a colleague in Shanghai is 1:00 UTC, not 15:00 UTC.

CDT has two meanings as well: Central Daylight Time (UTC−5, the US and Canadian summer form) and Cuba Daylight Time (UTC−4). Mexico abolished daylight saving time for most of the country in October 2022, so Mexico City now stays on CST all year. Some municipalities on the US border still follow the US dates: Matamoros and Ojinaga switch between CST and CDT, while Ciudad Juárez and Tijuana use Mountain and Pacific time.

Where and when CST is used

15 zones use CST all year. 11 zones use it for part of the year only, switching to daylight saving time in the other months. Computed from tzdata under the current rules.

Other meanings of CST

When a time arrives with only these letters, look at where the sender is, or ask for the UTC offset. Calendars and programs should never guess a zone from an abbreviation: the IANA database’s own documentation calls abbreviations ambiguous in practice.

How long CST has been used

In the tzdata record, Chicago has used CST since 1883, Knox has used CST since 1883 and Tell City has used CST since 1883.

CST in the past

Zones whose tzdata history shows CST before 2025 but that no longer use it:

• America/Winnipeg (Winnipeg): 1887–2024
• America/Havana (Havana): 1925–2024
• America/Ciudad_Juarez (Ciudad Juárez): 1927–2022
• America/Cancun (Cancún): 1922–2015
• America/Indiana/Petersburg (Petersburg): 1883–2007
• America/Indiana/Vincennes (Vincennes): 1883–2007
• America/Indiana/Winamac (Winamac): 1883–2007
• America/Cambridge_Bay (Cambridge Bay): 1999–2001
• America/Kentucky/Monticello (Monticello): 1883–2000
• America/Iqaluit (Iqaluit): 1999–2000
• Asia/Shanghai (Shanghai): 1900–1991
• Asia/Taipei (Taipei): 1895–1979

CST converted to other zones

Every column is a fixed offset, so this table is valid on any date. Remember that the regions behind some columns switch to summer time (EST to EDT, CET to CEST, GMT to BST); the clock in those cities is then an hour later than the column.

Related zones and conversions

• CDT time
• America/Chicago time zone
• UTC−6 time
• CST to IST
• CST to EST
• CST to UTC
• IST to CST
• Time zones of the world
• Daylight saving time
• Time zone converter