Costa Rica time zone history
On standard time, clocks at Costa Rica run 24 minutes behind local mean solar time, the largest gap of the 11 zones on UTC−6 standard time whose clocks run behind the sun. Daylight saving time was used in 4 years since 1970, last in 1992; under the current rules the clocks no longer change.
UTC−6
Standard time is UTC−6 (CST) all year under the current rules.
Summer time in 4 of 57 years since 1970
Before 1970
Standard time changes
| Date | Change | New standard time | Clock label |
|---|---|---|---|
| Before 1970 | |||
| January 1, 1890 | Local mean time (UTC−5:36:13) replaced | UTC−5:36:13 | SJMT |
| January 15, 1921 | Standard time back 24 minutes | UTC−6 | CST |
Daylight saving periods
| Years | Clocks go forward | Clocks go back | Shift and labels |
|---|---|---|---|
| 1979–1980 | fourth Sunday in February, 00:00 | first Sunday in June, 00:00 | 1 hour, CST to CDT |
| 1991 | January 19 | July 1 | 1 hour, CST to CDT |
| 1992 | January 18 | March 15 | 1 hour, CST to CDT |
Also on UTC−6
Nicaragua, Honduras, El Salvador, Guatemala, Belize, Galápagos Islands (Ecuador), Mérida (Mexico), Mexico City (Mexico), Matamoros (Mexico) and Monterrey (Mexico) (nearest first; 17 more on the list of offsets).
Clocks next door since 1970
- Nicaragua (344 km): same time except 2,905 days in 1973–1975, 1979, 1980, 1991–1997, 2005 and 2006.
- Panama (511 km): usually 1 hour ahead; different on 416 days in 1979, 1980, 1991 and 1992.
- Honduras (575 km): same time except 802 days in 7 different years between 1979 and 2006.
- El Salvador (697 km): same time except 710 days in 1979, 1980, 1987, 1988, 1991 and 1992.
- Guatemala (873 km): same time except 753 days in 8 different years between 1973 and 2006.
How it compares
Standard time has stayed at UTC−6 since 1921.