GMT/BST
Greenwich Mean Time
GMT +0
12am
3am
6am
9am
12pm
3pm
6pm
9pm
BST is not used on this date
This converter uses GMT (GMT +0), the offset London uses on this date. Open the GMT converter.
Illinois, USA
CST
12am
3am
6am
9am
12pm
3pm
6pm
9pm

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

Time Difference

Greenwich Mean Time is 6 hours ahead of CST (Central Standard Time)
12:00 pm12:00 in GMT is 6:00 am06:00 in Chicago, IL, USA

GMT to Chicago call time
Best time for a conference call or a meeting is between 3pm-5pm in GMT which corresponds to 9am-11am in Chicago

12:00 pm12:00 Greenwich Mean Time (GMT). Offset UTC 0:00 hours
6:00 am06:00 CST (Central Standard Time) (Chicago, IL, USA). Offset UTC -6:00 hours

12:00 pm12:00 GMT / 6:00 am06:00 Chicago, IL, USA

GMTChicago, IL, USA
12am (midnight)6pm
1am7pm
2am8pm
3am9pm
4am10pm
5am11pm
6am12am (midnight)
7am1am
8am2am
9am3am
10am4am
11am5am
12pm (noon)6am
1pm7am
2pm8am
3pm9am
4pm10am
5pm11am
6pm12pm (noon)
7pm1pm
8pm2pm
9pm3pm
10pm4pm
11pm5pm
00:0018:00
01:0019:00
02:0020:00
03:0021:00
04:0022:00
05:0023:00
06:0000:00
07:0001:00
08:0002:00
09:0003:00
10:0004:00
11:0005:00
12:0006:00
13:0007:00
14:0008:00
15:0009:00
16:0010:00
17:0011:00
18:0012:00
19:0013:00
20:0014:00
21:0015:00
22:0016:00
23:0017:00

British Summer Time

Offset: BST is 1 hour ahead Greenwich Mean Time (GMT) and is used in Europe

Countries using this time zone: Britain (UK), Guernsey, Isle of Man, Jersey

Principal Cities: The largest city in the BST time zone is London in United Kingdom, with about 7.557 million people. Other major cities in this time zone include Birmingham, Glasgow, Liverpool, Saint Helier.

Greenwich Mean Time (GMT) originally referred to the mean solar time at the Royal Observatory in Greenwich, London. It is now often used to refer to Coordinated Universal Time (UTC) when this is viewed as a time zone, and in casual use for the most parts it is the same. In military GMT is known as Zulu time.Greenwich Mean Time was the same as Universal Time (UT), until the introduction of UTC in 1972 a standard astronomical concept used in many technical fields.

BST Time Zone Geo Map
BST timezone map

BST representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • +01 - basic short
  • +0100 - basic
  • +01:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • +0100 - sign character (+) followed by a four digit time providing hours (01) and minutes (00) of the offset. Indicates an offset of one hour to the east of the zero meridian.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Alpha - Military abbreviation for BST
  • A - short form of 'Alpha'
IANA/Olson: Reflects BST time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • Europe/Belfast
  • Europe/Guernsey
  • Europe/Isle_of_Man
  • Europe/Jersey
  • Europe/London
  • GB
  • GB-Eire
BST Abbreviation: Several time zones share BST abbreviation and it could refer to these time zones
  • British Summer Time - UTC +1
  • Bangladesh Standard Time - UTC +6
  • Bougainville Standard Time - UTC +11
Time zones with the GMT +1 offset:
  • BST - British Summer Time
  • CET - Central European Time
  • IST - Irish Standard Time
  • WEST - Western European Summer Time
  • A - Alpha Time Zone
  • CET - Central European Time
  • MEZ - Mitteleuropäische Zeit
  • WAT - West Africa Time
  • WST - Western Sahara Summer Time
  • BMT - Biel Mean Time

Chicago Information

Time Zone

Abbreviation / Name
CDT - Central Daylight Time
CST - Central Standard Time
UTC / GMT Offset
-5:00 hours during Central Daylight Time, currently in use.
-6:00 hours during Central Standard Time.
Daylight Saving Time Change
+1:00 hour - DST is in use
Daylight Saving Time Starts
Daylight saving time clock moves forward for one hour from 2am to 3amSunday, March 8, 2026 at 2:00 am local time. DST starts annually on the 2nd Sunday of March. Clocks are turned forward 1 hour to Sunday, March 8, 2026 at 3:00 am local daylight time instead. Also called Spring Forward or Summer Time.
Daylight Saving Time Ends
Daylight saving time clock moves back for one hour from 2am to 1amSunday, November 1, 2026 at 2:00 am local time. DST ends annually on the 1st Sunday of November. Clocks are turned backward 1 hour to Sunday, November 1, 2026 at 1:00 am local standard time instead. Also called Fall Back or switch to Winter Time.

Chicago Facts

Country
USA
State
Illinois
Alternative Names
CHI, Cekaga, Chi-ka-ko, Chi-kâ-kô, Chicago, Chicagu, Chikago, Chykaga, Cikaga, Cikago, Cikaqo, E-Chicago, Kikako, Shikago, Sicagum, Sikago, The Windy City, Tsikago, Windy City, chikhako, cikago, cikako, shikago, shkagw, shykaghw, shykagw, shykajw, shyqgw, sikago, sikkagea, syqgw, zhi jia ge, Çikago, Çikaqo, Ĉikago, Čikaga, Čikago, Čikāga, Čėkaga, Şikago, Σικάγο, Чикаго, Чикаґо, Чыкага, Չիկագո, שיקאגא, שיקגו, شيكاجو, شيكاغو, شکاگو, شیکاگو, شیکاگۆ, ܫܝܩܓܘ, शिकागो, শিকাগো, ਸ਼ਿਕਾਗੋ, சிகாகோ, చికాగో, ಶಿಕಾಗೊ, ഷിക്കാഗോ, ชิคาโก, ရှီကာဂိုမြို့, ჩიკაგო, ሺካጎ, ᓰᖄᑯ, Ṣìkágò, シカゴ, 芝加哥, 시카고, 𐍃𐌾𐌹𐌺𐌰𐌲𐍉
Population
2,720,546
Currency
Dollar (USD)
Geographic Coordinates
41° 51' N Latitude / 87° 39' W Longitude
International Dialing Code
+1