The annual public holiday celebrates the establishment of Otago's provincial government on March 23, 1852.
Despite that date, the anniversary is officially celebrated on the closest Monday, which this year was March 24.
But many observe it at Easter, which in the past has left many residents wondering which public services and businesses would recognise the annual holiday on Monday.
Dunedin resident Jan Parkinson said she had given up trying to guess which stores would be open.
''Our province is the only place in New Zealand that seems to be a darn mess.
''If it's a public holiday - people should take it on the day.
''It's argued over every year, but nothing ever changes.
''People have come to treat it like a lottery.''
It did not seem to bother visitors to the city.
David Sewell, of Ashburton, said the public holiday was well publicised by accommodation providers in the city and visitors were warned some stores and services would not be open.
He was down to celebrate a birthday in Dunedin at the weekend and had no trouble finding somewhere to have breakfast yesterday morning.
''If it's open, you go in. If it's closed, you don't - it's pot luck.''
Moana Pool, the iSite visitors centre, Toitu Early Settlers Museum, the Chinese Garden and Dunedin Public Art Gallery were all open as normal, and the Green Island Landfill, refuse collection and bus services also operated as normal.
However, public libraries and banks were closed.
Major retailers and supermarkets throughout the city were open, as were many cafes, bars and restaurants.
Schools in the city were also closed, despite the Ministry of Education allowing individual schools to decide whether to observe the public holiday on Monday or at Easter.