Time Zone History

Time zone history in South America

41 zones of the tz database have their reference point in South America. They use 4 different standard times today; the most common is UTC−3, kept by 26 zones. 1 still change their clocks during the year. 35 used daylight saving time at some point since 1970 and no longer do, most recently in 2025. The record with the most changes of standard time since 1970 is San Luis, with 8 times.

Standard times in use

UTC−21 zoneUTC−326 zonesUTC−49 zonesUTC−55 zonesUTC−21 zoneUTC−326 zonesUTC−49 zonesUTC−55 zones

Every zone, with its clock changes since 1970

The strip shows 1970 to 2028; amber marks years with seasonal clock changes.

ZoneStandard timeClock changes todayNew standard times since 19701970 to 2028
Fernando de Noronha, BrazilUTC−2no (last 2002)0
Araguaína, BrazilUTC−3no (last 2013)0
ParaguayUTC−3no (last 2024)3
Bahia, BrazilUTC−3no (last 2012)0
Belém, BrazilUTC−3no (last 1988)0
Buenos Aires, ArgentinaUTC−3no (last 2009)2
Catamarca, ArgentinaUTC−3no (last 2008)6
French GuianaUTC−3no0
Cordoba, ArgentinaUTC−3no (last 2009)4
Coyhaique, ChileUTC−3no (last 2025)1
Fortaleza, BrazilUTC−3no (last 2002)0
Jujuy, ArgentinaUTC−3no (last 2008)4
La Rioja, ArgentinaUTC−3no (last 2008)6
Maceió, BrazilUTC−3no (last 2002)0
Mendoza, ArgentinaUTC−3no (last 2008)6
UruguayUTC−3no (last 2015)0
SurinameUTC−3no1
Punta Arenas, ChileUTC−3no (last 2016)1
Recife, BrazilUTC−3no (last 2002)0
Rio Gallegos, ArgentinaUTC−3no (last 2008)4
Salta, ArgentinaUTC−3no (last 2008)4
San Juan, ArgentinaUTC−3no (last 2008)6
San Luis, ArgentinaUTC−3no (last 2009)8
Santarém, BrazilUTC−3no (last 1988)1
São Paulo, BrazilUTC−3no (last 2019)0
Tucumán, ArgentinaUTC−3no (last 2009)6
Ushuaia, ArgentinaUTC−3no (last 2008)4
Boa Vista, BrazilUTC−4no (last 2000)0
Campo Grande, BrazilUTC−4no (last 2019)0
VenezuelaUTC−4no2
Cuiabá, BrazilUTC−4no (last 2019)0
GuyanaUTC−4no2
BoliviaUTC−4no0
Manaus, BrazilUTC−4no (last 1994)0
Porto Velho, BrazilUTC−4no (last 1988)0
Santiago, ChileUTC−4yes0
ColombiaUTC−5no (last 1993)0
Eirunepé, BrazilUTC−5no (last 1994)2
Guayaquil, EcuadorUTC−5no (last 1993)0
PeruUTC−5no (last 1994)0
Rio Branco, BrazilUTC−5no (last 1988)2