AST
Atlantic Standard Time
GMT -4
12am
3am
6am
9am
12pm
3pm
6pm
9pm
Brazil
BRT
12am
3am
6am
9am
12pm
3pm
6pm
9pm

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

Time Difference

Atlantic Standard Time is 1 hour behind BRT (Brasilia Time)
8:00 am08:00 in AST is 9:00 am09:00 in Sao Paulo, Brazil

AST to São Paulo call time
Best time for a conference call or a meeting is between 9am-4pm in AST which corresponds to 10am-5pm in São Paulo

8:00 am08:00 Atlantic Standard Time (AST). Offset UTC -4:00 hours
9:00 am09:00 BRT (Brasilia Time) (Sao Paulo, Brazil). Offset UTC -3:00 hours

8:00 am08:00 AST / 9:00 am09:00 Sao Paulo, Brazil

ASTSao Paulo, Brazil
12am (midnight)1am
1am2am
2am3am
3am4am
4am5am
5am6am
6am7am
7am8am
8am9am
9am10am
10am11am
11am12pm (noon)
12pm (noon)1pm
1pm2pm
2pm3pm
3pm4pm
4pm5pm
5pm6pm
6pm7pm
7pm8pm
8pm9pm
9pm10pm
10pm11pm
11pm12am (midnight)
00:0001:00
01:0002:00
02:0003:00
03:0004:00
04:0005:00
05:0006:00
06:0007:00
07:0008:00
08:0009:00
09:0010:00
10:0011:00
11:0012:00
12:0013:00
13:0014:00
14:0015:00
15:0016:00
16:0017:00
17:0018:00
18:0019:00
19:0020:00
20:0021:00
21:0022:00
22:0023:00
23:0000:00

Atlantic Standard Time

Offset: AST is 4 hours behind Greenwich Mean Time (GMT) and is used in North America

Countries using this time zone: Antigua & Barbuda, Anguilla, Aruba, Barbados, St Barthelemy, Bermuda, Caribbean NL, Canada, Curaçao, Dominica, Dominican Republic, Grenada, Greenland, Guadeloupe, St Kitts & Nevis, St Lucia, St Martin (French), Martinique, Montserrat, Puerto Rico, St Maarten (Dutch), Trinidad & Tobago, St Vincent, Virgin Islands (UK), Virgin Islands (US)

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

French: HNA - Heure Normale de l'Atlantique

Spanish: AST - Tiempo Estándar del Atlántico

AST Time Zone Geo Map
AST timezone map

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).

Daylight saving time clock moves back for one hour from 2am to 1amStart: Atlantic Standard Time (AST) 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 on the first Sunday of November.

Daylight saving time clock moves forward for one hour from 2am to 3amEnd: Atlantic Standard Time (AST) 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 ends annually on the second Sunday of March.

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
  • FKT - Falkland Island Time
  • GYT - Guyana Time
  • HLV - Hora Legal de Venezuela
  • PYT - Paraguay Time
  • Q - Quebec Time Zone
  • VET - Venezuelan Standard Time

São Paulo Information

Time Zone

Abbreviation / Name
BRT - Brasília time
UTC / GMT Offset
-3:00 hours during Brasília time, currently in use.

São Paulo Facts

Country
Brazil
Alternative Names
SAO, Sampa, San Paolo, San Paul ed Brasil, San Paulas, San Paulo, San Paulu, San Paulu du Brasili, San Paulu dû Brasili, San Pauluw, San Pawlo, San Polo del Braxil, San Poulo, San Poło del Braxil, San Pàul ëd Brasil, San-Paulo, San-Paulu, San-Paŭlo, Sanpaulu, Sao Paolo, Sao Paulo, Sao Paulo capital, Saun Paulu, Sawo Palo, Sawo Pålo, São Paolo, São Paulo, São Paulo capital, Urbs Paulistana, cavo pavulo, sa'o pa'ulo, sa'o paulo, samu pa'ulu, sangpaollo, sangpaollu, sangpaullo, sangpaullu, sankt. paulos, sanpauro, savea pealea, savo palo, saw bawlw, saw palw, saw pwlw, saywpaywlw, sea pea lu, sheng bao luo, Σάο Πάολο, Сан Пауло, Сан Паулу, Сан-Паулу, Сан-Паўлу, Сао Паоло, Сао Пауло, Սան Պաուլու, סאו פאולא, סאו פאולו, ساؤ پالو, ساؤ پولو, سائوپائولو, ساو باولو, ܣܐܘ ܦܐܘܠܘ, ސައޮ ޕައުލޯ, साओ पाउलो, সাঁউ পাউলু, সাও পাউলো, சாவோ பாவுலோ, శఒ పౌలొ, ಸಾವೊ ಪಾಲೊ, സാവോ പോളോ, เซาเปาลู, ဆောပိုလိုမြို့, სან-პაულუ, ሳው ፓውሉ, サンパウロ, 聖保羅, 상파올로, 상파올루, 상파울로, 상파울루
Population
10,021,295
Currency
Real (BRL)
Geographic Coordinates
23° 32' S Latitude / 46° 38' W Longitude
International Dialing Code
+55