Daylight saving time in Brazil

Daylight saving time in Brazil (called horário de verão—"summer time"—in Portuguese) was first adopted in 1931. Initially, it applied to the whole country (with an exception in part of 1963); since 1988, it started being used only in part of the country.

The duration and regional applicability of DST has varied over the years (see for details). As of 2013, DST is used only in the southern region (the states of Rio Grande do Sul, Santa Catarina, Paraná), the southeast region (the states of São Paulo, Rio de Janeiro, Espirito Santo, Minas Gerais), and the central-west region (the states of Goiás, Mato Grosso and Mato Grosso do Sul, and the Distrito Federal).

Formerly, starting and ending dates were variable, but in 2008, a decree (No. 6558 of 9 September 2008) established a permanent rule: DST starts at 00:00 on the third Sunday in October and ends at 00:00 on the third Sunday in February—unless the latter falls during Carnaval: in this case, the end of DST is postponed by one week. Near-past and near-future years in which the end of DST is scheduled to be postponed are 2012, 2015, 2023, 2026, 2034, and 2037.

Before 2008, there were no fixed start and end dates for summer time, nor which states should or should not follow it; they were decided every year by one or more decrees, sometimes published very close to their start date.

On 8 September 2008, Presidential Decree n. 6.558 established fixed start and end dates and listed the Brazilian federative units that will annually observe daylight saving time. Later, Presidential Decree n. 7.584, of 13 October 2011, added the state of Bahia to the list of DST observing territories. In 2012, the observing states were changed again: Bahia was excluded from daylight saving time, and was included for the first time. Tocantins stopped observing daylight saving time in 2013.

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