Updating current time…
S
12am
3am
6am
9am
12pm
3pm
6pm
9pm
CST/CDT
UTC−6
same time
12am
3am
6am
9am
12pm
3pm
6pm
9pm
Central Time is on standard time: CST (UTC−6) until Sun, Mar 14, 2027.

Quick answers

Selected conversion

10:00 am10:00 S (UTC-6), Nov 1, 2026 = 10:00 am10:00 CST (UTC-6), Nov 1, 2026

S and CST have the same local time.

S and CDT examples

These examples always use S (UTC-6) and CDT (UTC-5). They stay the same when you change the date or time above. The selected conversion may differ when daylight saving time applies.

S is 1 hour behind CDT.

How the time difference changes

For most of the year, S is 1 hour behind CDT. From Nov 1, 2026 to Mar 14, 2027, S and CST have the same time.

For most of the year, working hours of 9:00 am to 6:00 pm in S correspond to 10:00 am to 7:00 pm in CDT. At other times of the year, working hours of 9:00 am to 6:00 pm in S correspond to 9:00 am to 6:00 pm in CST.For most of the year, working hours of 09:00 to 18:00 in S correspond to 10:00 to 19:00 in CDT. At other times of the year, working hours of 09:00 to 18:00 in S correspond to 09:00 to 18:00 in CST.

Compare S time with CDT time, including current local time, UTC offsets, time difference, daylight saving changes, working hours, and shareable meeting times.

Time Difference

Sierra Time Zone and Central Standard Time have the same local time.
10:00 am10:00 in S is 10:00 am10:00 in CST

S to CST call time
Best time for a conference call or a meeting is between 9am-6pm09:00-18:00 in S which corresponds to 9am-6pm09:00-18:00 in CST

10:00 am10:00 Sierra Time Zone (S). Offset UTC -6:00 hours
10:00 am10:00 Central Standard Time (CST). Offset UTC -6:00 hours

10:00 am10:00 S / 10:00 am10:00 CST

Choose an hour to update the converter. Day labels such as “next day” or “+1” are relative to the selected date in the first column. Use Up and Down arrow keys, Home or End to move between hours, then Enter or Space to select.

Hourly time comparison
SCST
1:00am CDT UTC-5
1:00am
2:00am
3:00am
4:00am
5:00am
6:00am
7:00am
8:00am
9:00am
10:00am
11:00am
12:00pm
1:00pm
2:00pm
3:00pm
4:00pm
5:00pm
6:00pm
7:00pm
8:00pm
9:00pm
10:00pm
11:00pm
01:00 CDT UTC-5
01:00
02:00
03:00
04:00
05:00
06:00
07:00
08:00
09:00
10:00
11:00
12:00
13:00
14:00
15:00
16:00
17:00
18:00
19:00
20:00
21:00
22:00
23:00

Sierra Time Zone

Offset: S is 6 hours behind Greenwich Mean Time (GMT).

Countries using this time zone: Belize, Canada, Chile, Costa Rica, Ecuador, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, United States

Principal Cities: The largest city in the S time zone is Mexico City in Mexico, with about 12.294 million people. Other major cities in this time zone include Chicago, Houston, Puebla, Santiago de Querétaro.

Daylight Saving: Some places on Sierra Time Zone (S) keep the same time all year, while others use S for only part of the year and change their clocks for daylight saving time; see upcoming clock changes worldwide.

Map of the areas on Sierra Time Zone (S)
S all year S part of the year

Today some of the lighter areas are on UTC−7 (MST).

S representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • -06 - basic short
  • -0600 - basic
  • -06:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • -0600 - sign character (-) followed by a four digit time providing hours (06) and minutes (00) of the offset. Indicates an offset of six hours to the west of the zero meridian.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Sierra - Military abbreviation for S
  • S - short form of 'Sierra'
Time zones with the GMT -6 offset:
  • CST - Central Standard Time
  • CT - Central Time
  • MDT - Mountain Daylight Time
  • EAST - Easter Island Standard Time
  • GALT - Galapagos Time
  • S - Sierra Time Zone

Central Daylight Time

Offset: CDT is 5 hours behind Greenwich Mean Time (GMT).

Countries using this time zone: Canada, Mexico, United States

Principal Cities: The largest city in the CDT time zone is Chicago in the United States, with about 2.664 million people. Other major cities in this time zone include Houston, San Antonio, Dallas, Fort Worth.

French: HAC - Heure Avancée du Centre

Spanish: CT - Zona Centro

Map of the areas on Central Daylight Time (CDT)
CDT part of the year

Today the shaded areas are on UTC−6 (Central Standard Time).

Daylight Saving: Central Daylight Time (CDT) is a daylight saving/summer time zone, but some places set clocks back one hour during winter and observe Central Standard Time (CST).

123456789101112End: Central Daylight Time (CDT) ended on Sunday, November 1, 2026 at 2:00 am02:00 local time and clocks were set one hour back to Sunday, November 1, 2026, 1:00 am01:00 local standard time instead. Daylight saving ends annually on the first Sunday of November.

123456789101112Start: Central Daylight Time (CDT) starts on Sunday, March 14, 2027 at 2:00 am02:00 local time and clocks are set one hour forward to Sunday, March 14, 2027, 3:00 am03:00. Daylight saving starts annually on the second Sunday of March.

See USA daylight saving time and upcoming clock changes worldwide.

CDT representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • -05 - basic short
  • -0500 - basic
  • -05:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • -0500 - sign character (-) followed by a four digit time providing hours (05) and minutes (00) of the offset. Indicates an offset of five hours to the west of the zero meridian.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Romeo - Military abbreviation for CDT
  • R - short form of 'Romeo'
IANA/Olson: Reflects CDT time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • America/Chicago
  • America/Indiana/Knox
  • America/Indiana/Tell_City
  • America/Knox_IN
  • America/Matamoros
  • America/Menominee
  • America/North_Dakota/Beulah
  • America/North_Dakota/Center
  • America/North_Dakota/New_Salem
  • America/Ojinaga
  • America/Rainy_River
  • America/Rankin_Inlet
  • America/Resolute
  • America/Winnipeg
  • CST6CDT
  • Canada/Central
  • US/Central
  • US/Indiana-Starke
CDT Abbreviation: Several time zones share CDT abbreviation and it could refer to these time zones
  • Central Daylight Time - UTC -5
  • Cuba Daylight Time - UTC -4
Time zones with the GMT -5 offset:
  • CDT - Central Daylight Time
  • EST - Eastern Standard Time
  • ET - Eastern Time
  • COT - Colombia Time
  • CST - Cuba Standard Time
  • EASST - Easter Island Summer Time
  • ECT - Ecuador Time
  • PET - Peru Time
  • R - Romeo Time Zone