A couple has been ordered to pay close to $3 million after a legal wrangle over a luxury Auckland home they failed to buy.

John Goodman and Deborah Rattray had an unconditional agreement to buy the Milford Beach home from James and June Messenger for almost $6 million in 2006 and make payments over the next two years.

After a long-running legal dispute over the settlement date, payments were not made and the Messengers cancelled the agreement and resold the house in 2009 for $4.4 million.

When they failed in a High Court bid to force Mr Goodman and Ms Rattray to pay the difference in sale prices as well as interest and costs, they took their case to the Court of Appeal.

In a decision issued on Friday, Justices Stevens, French and Venning said Mr Goodman and Ms Rattray, who did not attend the appeal hearing and were not represented, had breached the contract by making no payment and ordered them to pay the Messengers $2.88 million, which includes interest and costs.

They said the substantial loss appeared to reflect a change in market conditions between 2006 and 2009.

"In our view the loss suffered by the Messengers on the resale of the property was as claimed a direct consequence of Mr Goodman and Ms Rattray's failure to settle."