Updating current time…
MexicoEST
UTC−5
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3am
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ADT/AST
UTC−3
2h ahead
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Atlantic Time is on daylight saving time: ADT (UTC−3) until Sun, Nov 1.

Quick answers

Selected conversion

7:00 am07:00 EST (UTC-5), Oct 16, 2026 = 9:00 am09:00 ADT (UTC-3), Oct 16, 2026

Cozumel is 2 hours behind ADT.

How the time difference changes

For most of the year, Cozumel is 2 hours behind ADT. From Nov 1, 2026 to Mar 14, 2027, Cozumel is 1 hour behind AST.

For most of the year, working hours of 9:00 am to 6:00 pm in Cozumel correspond to 11:00 am to 8:00 pm in ADT. At other times of the year, working hours of 9:00 am to 6:00 pm in Cozumel correspond to 10:00 am to 7:00 pm in AST.For most of the year, working hours of 09:00 to 18:00 in Cozumel correspond to 11:00 to 20:00 in ADT. At other times of the year, working hours of 09:00 to 18:00 in Cozumel correspond to 10:00 to 19:00 in AST.

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

Time Difference

EST (Eastern Standard Time) is 2 hours behind Atlantic Daylight Time.
7:00 am07:00 in Cozumel, Mexico is 9:00 am09:00 in ADT

Cozumel to ADT call time
Best time for a conference call or a meeting is between 9am-4pm09:00-16:00 in Cozumel which corresponds to 11am-6pm11:00-18:00 in ADT

7:00 am07:00 EST (Eastern Standard Time) (Cozumel, Mexico). Offset UTC -5:00 hours
9:00 am09:00 Atlantic Daylight Time (ADT). Offset UTC -3:00 hours

7:00 am07:00 Cozumel, Mexico / 9:00 am09:00 ADT

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Hourly time comparison
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Cozumel Time Zone and Facts

Time Zone

Abbreviation / Offset
EST – Eastern Standard Time, UTC-5 (no daylight saving time)

Cozumel Facts

Country
Mexico
Alternative Names
CZM, Conzumel, Cozumel, San Miguel Cozumel, San Miguel de Cozumel
Population
77,236
Currency
Peso (MXN)
Geographic Coordinates
20° 30' N Latitude / 86° 56' W Longitude
International Dialing Code
+52

Atlantic Standard Time

Offset: AST is 4 hours behind Greenwich Mean Time (GMT).

Countries using this time zone: Anguilla, Antigua and Barbuda, Aruba, Barbados, Bermuda, British Virgin Islands, Canada, Caribbean Netherlands, Curaçao, Dominica, Dominican Republic, Greenland, Grenada, Guadeloupe, Martinique, Montserrat, Puerto Rico, Saint Barthélemy, Saint Kitts and Nevis, Saint Lucia, Saint Martin, Saint Vincent and the Grenadines, Sint Maarten, Trinidad and Tobago, US Virgin Islands

Principal Cities: The largest city in the AST time zone is Santo Domingo in the Dominican Republic, with about 2.202 million people. Other major cities in this time zone include Santiago de los Caballeros, Halifax, San Juan, San Pedro de Macorís.

French: HNA - Heure Normale de l'Atlantique

Spanish: AST - Tiempo Estándar del Atlántico

Map of the areas on Atlantic Standard Time (AST)
AST all year AST part of the year

Today the lighter areas are on UTC−3 (ADT).

Daylight Saving: This is a standard time zone. During summer, some places set clocks forward one hour for daylight saving time and observe Atlantic Daylight Time (ADT).

123456789101112End: Atlantic Standard Time (AST) ended on Sunday, March 8, 2026 at 2:00 am02:00 local time and clocks were set one hour forward to Sunday, March 8, 2026, 3:00 am03:00 local daylight time instead. Standard time ends annually on the second Sunday of March.

123456789101112Start: Atlantic Standard Time (AST) starts on Sunday, November 1, 2026 at 2:00 am02:00 local time and clocks are set one hour back to Sunday, November 1, 2026, 1:00 am01:00. Standard time starts annually on the first Sunday of November.

See Canada daylight saving time and upcoming clock changes worldwide.

AST representations, usage and related time zones

W3C/ISO-8601: International standard covering representation and exchange of dates and time-related data
  • -04 - basic short
  • -0400 - basic
  • -04:00 - extended
Email/RFC-2822: Internet Message Format Date Standard, typically used for timestamps in email headers
  • -0400 - sign character (-) followed by a four digit time providing hours (04) and minutes (00) of the offset. Indicates an offset of four hours to the west of the zero meridian.
Military/NATO: Used by the U.S. military, Chinese military and others
  • Quebec - Military abbreviation for AST
  • Q - short form of 'Quebec'
IANA/Olson: Reflects AST time zone boundaries defined by political bodies, primarily intended for use with computer programs and operating systems
  • America/Anguilla
  • America/Antigua
  • America/Aruba
  • America/Barbados
  • America/Blanc-Sablon
  • America/Curacao
  • America/Dominica
  • America/Glace_Bay
  • America/Goose_Bay
  • America/Grenada
  • America/Guadeloupe
  • America/Halifax
  • America/Kralendijk
  • America/Lower_Princes
  • America/Marigot
  • America/Martinique
  • America/Moncton
  • America/Montserrat
  • America/Port_of_Spain
  • America/Puerto_Rico
  • America/Santo_Domingo
  • America/St_Barthelemy
  • America/St_Kitts
  • America/St_Lucia
  • America/St_Thomas
  • America/St_Vincent
  • America/Thule
  • America/Tortola
  • America/Virgin
  • Atlantic/Bermuda
  • Canada/Atlantic
AST Abbreviation: Several time zones share AST abbreviation and it could refer to these time zones
  • Atlantic Standard Time - UTC -4
  • Arabia Standard Time - UTC +3
Time zones with the GMT -4 offset:
  • AST - Atlantic Standard Time
  • EDT - Eastern Daylight Time
  • AMT - Amazon Time
  • BOT - Bolivia Time
  • CDT - Cuba Daylight Time
  • CLT - Chile Standard Time
  • GYT - Guyana Time
  • HLV - Hora Legal de Venezuela
  • Q - Quebec Time Zone
  • VET - Venezuelan Standard Time