Several parties have expressed interest in a major dairy business in NSW ahead of its market listing next month.

New Zealand-owned Raleigh Dairy Holdings operates two farms at Yellow Rock and North Bank south of Coffs Harbour.

The selling agent, Colliers International, has confirmed there has been interest from potential overseas buyers.

In 2010 the operation, with a combined land area of 835 ha, was valued at $10 million.

The company supplies A1 and A2 milk to the nearby Norco Co-operative at Raleigh; 40 per cent of the 1,100 milking herd is certified A2.

Colliers International's agribusiness director, Rawdon Briggs, says the directors want to realise the asset and focus on their New Zealand operations.

"I have no opinion on the valuation from three years ago, or last week or whenever it might have been valued last, but it'll be put through the tender process and the market is the market and we expect good interest," he said.

Raleigh Dairy Holdings will be listed publicly on October 2 and will be sold through a two-round international tender process.

"A two-round process, whereby the best performers will be taken into the second round," he said.

"There will be a price wanting to be realised by the directors, nothing that I'm going to talk about today."

Raleigh Dairy Holdings has approval from the Bellingen Shire Council to expand operations at its North Bank Dairy.

In 2011, it withdrew a development application for expansion of its Yellow Rock site, following community concerns over the possibility of effluent run-off during floods polluting the adjacent Bellinger River.