Public holidays
1646, Brasil, Piauí
| # | Date | Public holiday |
|---|---|---|
| 1 | Monday, 1 January 1646 | New Year's Day |
| 2 | Tuesday, 13 February 1646 | Carnival Tuesday |
| 3 | Friday, 30 March 1646 | Good Friday |
| 4 | Saturday, 21 April 1646 | Tiradentes Day |
| 5 | Tuesday, 1 May 1646 | Labour Day |
| 6 | Thursday, 31 May 1646 | Corpus Christi |
| 7 | Friday, 7 September 1646 | Independence Day |
| 8 | Friday, 12 October 1646 | Our Lady of Aparecida |
| 9 | Friday, 19 October 1646 | Piauí Day |
| 10 | Friday, 2 November 1646 | All Souls' Day |
| 11 | Thursday, 15 November 1646 | Republic Proclamation Day |
| 12 | Saturday, 8 December 1646 | Immaculate Conception |
| 13 | Tuesday, 25 December 1646 | Christmas Day |