Public holidays in Heard Island and McDonald Islands are nationwide days off recognised by the government, when most banks, schools and government offices close and many businesses adjust their hours. They mark historical, cultural, religious or civic occasions and are a standard reference point for market research teams tracking regional business cycles working with Heard Island and McDonald Islands.

1 fixed-date public holiday is documented for Heard Island and McDonald Islands in the table above, on top of movable observances shown in the live calendar. The exact total varies year to year — some holidays fall on a fixed date, while Easter-based, Islamic-calendar or other lunar observances shift annually, and some are added by regional decree. See the live calendar above for the current list of upcoming and recently observed dates.

Official public holidays in Heard Island and McDonald Islands are enacted by national acts of parliament and published via heardisland.antarctica.gov.au. These non-working days carry legal status for banking, public administration, and employment compliance.

Australian national day observed for Heard Island and McDonald Islands. It falls on January 26 and carries official non-working status in Heard Island and McDonald Islands — see the statutory holidays table above for its closure impact and official source.

The official holidays table above lists fixed-date national public holidays mandated by law. Dynamic, movable observances (such as Eid or Easter) shift calendar dates annually based on lunar or religious computations — those dates are updated continuously in the live Google Calendar embed below.