The boss of Statistics NZ had been left questioning how such a new building could be so badly affected by Monday morning's quakes.
Chief executive Liz MacPherson said it appeared Statistics House had suffered structural damage to one corner of the building down the stadium end, partially affecting the corner of two floors.
"Based on the damage I have seen, the chances of us being back in the building in the near future are pretty remote."
She said the best assessment from the structural engineers was from several months to up to a year.
The building was purpose built for Statistics New Zealand in 2005 and the government department recently signed a 16-year lease on the building which is owned by CentrePort - a company owned by the Greater Wellington Regional Council and the Manawatu-Wanganui Regional Council.
It must now find temporary accommodation for its 500 staff.
In an earlier statement CentrePort chief executive Derek Nind said the company had been working on upgrades to the building based on advice from earthquake engineers before the quakes hit.
"We had just completed upgrades of the upper floors, which performed well.
"A small part of the ceiling on the ground floor and the first floor have partially dislodged after two concrete beams became separated from the exterior wall of the building."