That is the conclusion of a new report by agency Lisney, which studied the buildings available in 17 towns and cities in the country.
It suggested that the government's use of a vast amount of office space in Belfast is artificially affecting the value of it, which is now comparable to 20 years ago.
Indeed, Grade A stock in the capital is worth £12 per sq ft – a figure not seen for two decades.
Declan Flynn, managing director of the research body, said: "We need effective policies to protect our town centres and these should include rates reductions for all to locate in town centres rather than out of town."
Belfast's situation is far removed from that of London, which Richard Kauntze, chief executive of the British Council for Offices, recently described as "world class".
Posted by Darren Purse