Allied Farmers says the assets it acquired from Hanover and United Finance last year are now worth less than a third of the purchase price, and more revisions could be on the cards.
The assets - worth $396 million when the company acquired them in December - were revalued at $175.5 million in March, and now the company says that with bad loans and falling property values they are worth just $124 million.
Managing director Rob Alloway says the company has revalued between 60% and 70% of its loan book.
There have been other impairments, he says, mainly relating to the Auckland apartment market and some large-scale development properties that are yet to be rezoned.
Shares in Allied Farmers slipped almost 8% to 5.9 cents on Friday.