| # | Date | Public holiday |
|---|---|---|
| 1 | Friday, 1 January 1666 | New Year's Day |
| 2 | Wednesday, 6 January 1666 | Epiphany of the Lord |
| 3 | Friday, 19 March 1666 | Saint Joseph's Day |
| 4 | Thursday, 15 April 1666 | Maundy Thursday |
| 5 | Friday, 16 April 1666 | Good Friday |
| 6 | Monday, 19 April 1666 | Easter Monday |
| 7 | Saturday, 1 May 1666 | Labour Day |
| 8 | Sunday, 25 July 1666 | Saint James the Apostle |
| 9 | Sunday, 15 August 1666 | Assumption of the Virgin Mary |
| 10 | Monday, 1 November 1666 | All Saints' Day |
| 11 | Friday, 3 December 1666 | Saint Francis Xavier — Navarre Day / Saint Francis Xavier — Navarre Day |
| 12 | Monday, 6 December 1666 | Spanish Constitution Day |
| 13 | Wednesday, 8 December 1666 | Immaculate Conception |
| 14 | Saturday, 25 December 1666 | Nativity of the Lord |