The $54.5 million project at the former central Dunedin Warehouse site, in Maclaggan St, will house about 300 Dunedin-based regional council staff.
Port Otago acquired the building in 2021 and last year, the council-owned company and the council announced a 40-year lease agreement; initially for 20 years then two 10-year rights of renewal.
Construction was originally due to be completed by Christmas this year, but last month Port Otago chief executive Kevin Winders said the company was now targeting completion in the second half of next year.