The house at 50 Malone Park was at the centre of a legal battle after a businessman agreed to buy it at the height of the property boom but then refused to pay.
A high court ordered Nicholas McKenna to pay over £2m for the house last year despite claims the head of the Ballymena-based Galgorm group had pulled out of the deal.
The businessman had denied suggestions that the property crash thwarted any hopes of making a £500k profit on the house.
The offer was expected to make the six-bedroom Victorian property the highest-fetching residence on the market at the time.
A sale has now been agreed for the premises for the more humble sum of £825,000 according to Ulster Property Services.