A Ministry of Justice spokesman said the doors would open once the information technology system was ready.
Court services will be moved to High St while the ministry upgrades the historic Stuart St courthouse.
The main part of the category 1 heritage building, built in 1902, has been closed since December 2011 after an engineer's assessment found it was unstable.
Earthquake-strengthening work is due to go out for tender later this year.
The extensive engineering and strengthening work will take about two years, during which time the entire Stuart St complex will be closed.
The former CIB building in Dunbar St, housing coronial services, will also be closed and operations transferred to John Wickliffe House, which will continue to accommodate civil and family court.
Jury trials, list court and youth court will be held in the High St building.
Estimates based on previous engineering reports suggested an upgrade of the Stuart St courthouse under new Building Act requirements could cost between $3 million and $10 million.
The ministry spent about $10 million refurbishing the stone masonry courthouse in 2001.
Labour Dunedin North MP David Clark recently criticised the ministry for spending too much time deciding whether to upgrade the building.
He said if the decision had been made sooner, repairs could have been completed by now and the ministry would not have spent as much taxpayers' money on temporary facilities.
''There was no need to pussyfoot about. It feels like the amount that's been spent could have covered the costs of doing repairs if they had got on with it straight away,'' he said.
Dunedin lawyer Anne Stevens said it had been frustrating to see most of the courthouse empty for almost two years while the ministry spent money elsewhere.
''Why spend it twice?'' she asked.
She was relieved she would no longer have to travel to Invercargill for jury trials, but anticipated problems for people having to use court facilities in various locations around Dunedin.
As of June 30, the ministry had spent $3.97 million on John Wickliffe House, reconfiguring public areas at the Stuart St courthouse and the jury trial facility at 184 High St.
The amount comprises $3.39 million of capital expenditure and $580,000 operating costs.
Lease and construction costs, furniture, fixtures, fittings and relocation costs at John Wickliffe House and the Stuart St courthouse between December 2011 and June 30, 2013 totalled $1.064 million.
In response to Mr Clark's criticism, Courts Minister Chester Borrows said the ministry had made repairing the Dunedin courthouse a top priority, despite the need to repair Christchurch courts and deal with six other court closures due to safety concerns.
The Dunedin project had not been easy, he said.
''It has taken skilled engineers a considerable time to understand what is necessary, and how we can make the building safe without damaging its historic value.''
He said the High St facility was critical to the process of repairing the Stuart St courthouse, and would allow work to be done with minimal further disruption to services.
