The weekend in Buenos Aires is Saturday-Sunday. Public Holidays are:
January 1 (New Year's Day)
May 1 (Labor Day)
May 25 (First Argentine Government)
June 10 (National Sovereignty Day)
June 20 (Flag Day)
July 9 (Independence Day)
August 17 (Anniversary of the Death of General San Martín)
October 12 (Día de la Raza)
December 8 (Immaculate Conception Day), and
December 25 (Christmas).
Most tourist businesses and restaurants, however, will remain open during all but Christmas Eve, Christmas day and New Year's. Christmas Eve (24th December) tends to be a bigger celebration than Christmas day and family gatherings generally happen that night.