Time in Argentina

Argentina is located at a longitude that would naturally put it in the UTC−04:00 or UTC−05:00 time zone; however, it actually uses the UTC−03:00 time zone. Argentina determines whether to change clocks in observation of daylight saving time on a year-by-year basis, and individual provinces may opt out of the federal decision. At present, Argentina does not change clocks.^{[citation needed]}

Time zone map of South America

The Argentine Hydrographic Service^[1] maintains the official national time.

History

The first official standardization of time in Argentina took place on 31 October 1894, with establishment of UTC−04:00 as the nation's standard time.^[2] From 1920 to 1969, the official time switched biannually between UTC−04:00 as standard time in winter and UTC−03:00 as daylight saving time in summer.^[3] From 1974 to 1993, clocks advanced again, such that the official time switched biannually between UTC−03:00 as winter DST and UTC−02:00 as summer double DST.^[4] In 1993, the national time was fixed at UTC−03:00, called Argentina Time (ART;^[5][6] Spanish: hora oficial argentina, HOA). In 2007 and 2008, biannual switching between UTC–3:00 (winter DST) and UTC–2:00 (summer DST) resumed; in 2009, this was replaced again with year-round UTC–3:00 (permanent DST).^[7]

IANA time zone database

In the file zone.tab of the IANA time zone database Argentina has the following zones:

1. America/Argentina/Buenos_Aires – Buenos Aires (BA, CF)
2. America/Argentina/Cordoba – most locations (CD, CC, CR, ER, FO, MN, SF)
3. America/Argentina/Salta (SA, LP, NQ, RN)
4. America/Argentina/Jujuy – Jujuy (JY)
5. America/Argentina/Tucuman – Tucuman (TM)
6. America/Argentina/Catamarca – Catamarca (CT), Chubut (CH)
7. America/Argentina/La Rioja – La Rioja (LR)
8. America/Argentina/San Juan – San Juan (SJ)
9. America/Argentina/Mendoza – Mendoza (MZ)
10. America/Argentina/San Luis – San Luis (SL)
11. America/Argentina/Rio Gallegos – Santa Cruz (SC)
12. America/Argentina/Ushuaia – Tierra del Fuego (TF)
13. America/Argentina/Santiago_del_Estero (SE)

Full History

Full History of Timezone Changes since 1920

From 12:00 AM of the day	Adopted Time Zone	Until 11:59 of the day
01-05-1920	-4	30-11-1930
01-12-1930	-3	31-03-1931
01-04-1931	-4	14-10-1931
15-10-1931	-3	29-02-1932
01-03-1932	-4	31-10-1932
01-11-1932	-3	29-02-1933
01-03-1933	-4	31-10-1933
01-11-1933	-3	28-02-1934
01-03-1934	-4	31-10-1934
01-11-1934	-3	28-02-1935
01-03-1935	-4	31-10-1935
01-11-1935	-3	29-02-1936
01-03-1936	-4	31-10-1936
01-11-1936	-3	28-02-1937
01-03-1937	-4	31-10-1937
01-11-1937	-3	28-02-1938
01-03-1938	-4	31-10-1938
01-11-1938	-3	28-02-1939
01-03-1939	-4	31-10-1939
01-11-1939	-3	29-02-1940
01-03-1940	-4	30-06-1940
01-07-1940	-3	14-06-1941
15-06-1941	-4	14-10-1941
15-10-1941	-3	31-07-1943
01-08-1943	-4	14-10-1943
15-10-1943	-3	28-02-1946
01-03-1946	-4	30-09-1946
01-10-1946	-3	30-09-1963
01-10-1963	-4	14-12-1963
15-12-1963	-3	29-02-1964
01-03-1964	-4	14-10-1964
15-10-1964	-3	28-02-1965
01-03-1965	-4	14-10-1965
15-10-1965	-3	28-02-1966
01-03-1966	-4	14-10-1966
15-10-1966	-3	01-04-1967
02-04-1967	-4	30-09-1967
01-10-1967	-3	06-04-1968
07-04-1968	-4	05-10-1968
06-10-1968	-3	05-04-1969
06-04-1969	-4	04-10-1969
05-10-1969	-3	22-01-1974
23-01-1974	-2	30-04-1974
01-05-1974	-3	30-11-1988
01-12-1988	-2	04-03-1989
05-03-1989	-3	14-10-1989
15-10-1989	-2	03-03-1990
04-03-1990	-3	20-10-1990
21-10-1990	-2	02-03-1991
03-03-1991	-3	19-10-1991
20-10-1991	-2	29-02-1992
01-03-1992	-3	17-10-1992
18-10-1992	-2	06-03-1993
07-03-1993	-3	29-12-2007
30-12-2007	-2	15-03-2008
16-03-2008	-3	18-10-2008
19-10-2008	-2	14-03-2009
15-03-2009	-3	-present

^[8]

Notes

1.^ Date format: DD-MM-YYYY

2.^ Catamarca, Chubut, Jujuy, La Pampa, La Rioja, Mendoza, Neuquén, Río Negro, Salta, San Juan, San Luis, Santa Cruz and Tierra del Fuego, Antártida e Islas del Atlántico Sur, continued using -3 Timezone.