The Dominican Republic observes Atlantic Standard Time (UTC−4) year-round.
At midday April 1, 1933, Rafael Trujillo ordered a decree that established a national time zone for the Dominican Republic, which was set to five hours behind Greenwich Mean Time (GMT).
Prior to that, time in the Dominican Republic was governed by Santo Domingo Mean Time, which was 4 hours and 40 minutes behind GMT.
Data for Dominican Republic directly from zone.tab of the IANA time zone database; columns marked with * are the columns from zone.tab itself:[4]
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