MST
Mountain Standard Time
GMT -7
HST
Hawaii Standard Time
GMT -10

Time Difference

Mountain Standard Time is 3 hours ahead of Hawaii Standard Time
8:00 am08:00 in MST is 5:00 am05:00 in HST

MST to HST call time
Best time for a conference call or a meeting is between 11am-6pm in MST which corresponds to 8am-3pm in HST

8:00 am08:00 Mountain Standard Time (MST). Offset UTC -7:00 hours
5:00 am05:00 Hawaii Standard Time (HST). Offset UTC -10:00 hours

8:00 am08:00 MST / 5:00 am05:00 HST

MST HST
12am (midnight) 9pm
1am 10pm
2am 11pm
3am 12am (midnight)
4am 1am
5am 2am
6am 3am
7am 4am
8am 5am
9am 6am
10am 7am
11am 8am
12pm (noon) 9am
1pm 10am
2pm 11am
3pm 12pm (noon)
4pm 1pm
5pm 2pm
6pm 3pm
7pm 4pm
8pm 5pm
9pm 6pm
10pm 7pm
11pm 8pm
0:00 21:00
1:00 22:00
2:00 23:00
3:00 0:00
4:00 1:00
5:00 2:00
6:00 3:00
7:00 4:00
8:00 5:00
9:00 6:00
10:00 7:00
11:00 8:00
12:00 9:00
13:00 10:00
14:00 11:00
15:00 12:00
16:00 13:00
17:00 14:00
18:00 15:00
19:00 16:00
20:00 17:00
21:00 18:00
22:00 19:00
23:00 20:00

Mountain Standard Time

Offset: MST is 7 hours behind Greenwich Mean Time (GMT) and is used in North America

Countries: It is used in following countries: Canada, Mexico, United States

Principal Cities: The largest city in the MST timezone is Phoenix from USA with population about 1.446 million people. Other major cities in the area are Calgary, Edmonton, El Paso, Denver

French: HNR - Heure Normale des Rocheuses

Spanish: MT - Zona Pacífico

MST Time Zone Geo Map
MST timezone map

Daylight Saving: This is a standard timezone, however during summer some places switch clocks for one hour forward when daylight saving comes into effect and observe Mountain Daylight Time (MDT).

Daylight saving time clock moves back for one hour from 2am to 1amStart: Mountain Standard Time (MST) started on Sunday, November 2, 2025 at 2:00 am local time and clocks were set one hour back to Sunday, November 2, 2025, 1:00 am. Standard time starts annually the on first Sunday of November.

Daylight saving time clock moves forward for one hour from 2am to 3amEnd: Mountain Standard Time (MST) ends on Sunday, March 8, 2026 at 2:00 am local time and clocks are set one hour forward to Sunday, March 8, 2026, 3:00 am local daylight time instead. Standard time starts annually the on second Sunday of March.

MST representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • -07 - basic short
  • -0700 - basic
  • -07:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • -0700 - sign character (-) followed by a four digit time providing hours (07) and minutes (00) of the offset. Indicates seven hour and zero minutes time differences to the west of the zero meridian.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Tango - Military abbreviation for MST
  • T - short form of 'Tango'
IANA/Olson: Reflects MST time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • America/Boise
  • America/Cambridge_Bay
  • America/Ciudad_Juarez
  • America/Creston
  • America/Dawson
  • America/Dawson_Creek
  • America/Denver
  • America/Edmonton
  • America/Fort_Nelson
  • America/Hermosillo
  • America/Inuvik
  • America/Mazatlan
  • America/Phoenix
  • America/Shiprock
  • America/Whitehorse
  • America/Yellowknife
  • Canada/Mountain
  • Canada/Yukon
  • MST
  • MST7MDT
  • Mexico/BajaSur
  • Navajo
  • US/Arizona
  • US/Mountain
MST Abbreviation: Several time zones share MST abbreviation and it could refer to these time zones
  • Mountain Standard Time - UTC -7
  • Mauritius Standard Time - UTC +4
  • Moscow Standard Time - UTC +3
Time zones with the GMT -7 offset:
  • MST - Mountain Standard Time
  • PDT - Pacific Daylight Time
  • YST - Yukon Standard Time
  • T - Tango Time Zone

Hawaii Standard Time

Offset: HST is 10 hours behind Greenwich Mean Time (GMT) and is used in Pacific

Countries: It is used in following countries: United States

Principal Cities: The largest city in the HST timezone is Honolulu from USA with population about 371,657 people. Other major cities in the area are Pearl City, Hilo, Kailua, Waipahu

Daylight Saving: Hawaii Standard Time (HST) is not adjusted for daylight saving therefore HST remains the same through out the year. This means, unlike some time zones where the clock is set forward by one hour every summer and backward by one hour during winter to adjust for daylight saving, Hawaii Standard Time remains the same

HST Time Zone Geo Map
HST timezone map

HST representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • -10 - basic short
  • -1000 - basic
  • -10:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • -1000 - sign character (-) followed by a four digit time providing hours (10) and minutes (00) of the offset. Indicates ten hour and zero minutes time differences to the west of the zero meridian.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Whiskey - Military abbreviation for HST
  • W - short form of 'Whiskey'
IANA/Olson: Reflects HST time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • America/Adak
  • America/Atka
  • HST
  • Pacific/Honolulu
  • Pacific/Johnston
  • US/Aleutian
  • US/Hawaii
Time zones with the GMT -10 offset:
  • HAST - Hawaii-Aleutian Standard Time
  • CKT - Cook Island Time
  • HST - Hawaii Standard Time
  • TAHT - Tahiti Time
  • W - Whiskey Time Zone