A quarter of New Zealand real estate agents - almost 5000 - have deserted the industry in the past year during a bleak period of low sales.

Real Estate Agents Authority figures show almost 2000 Auckland agents have suspended their licences or let them lapse in the past 12 months.

Ray White agency chief executive Carey Smith said the slow real estate market had "pulverised" the sales force, who depended on commissions for their income.

"Sales are down, particularly in rural, and that had people seeking other employment," Mr Smith said.

"Independent contractors need to make sales to stay in business."

Agents are also facing much tougher scrutiny after new regulations were introduced to clamp down on "cowboys".

Nationwide, the number of agents fell from 17,809 to 13,092 - a drop of 26 per cent.

In Auckland, the drop was 25 per cent, from 7353 to 5539.

Real Estate Agents Authority chief executive Keith Manch said many in the industry considered that the number of agents could fall further, to as low as 10,000.

"In the economic situation, to maintain your licence you need to be pretty committed," Mr Manch said.

After peaking in late 2007, the real estate market suffered as house values fell throughout 2008.

The overall number of sales also dropped dramatically, from more than 9000 a month at the peak to fewer than 5000 a month - a fall of 44 per cent, according to Quotable Value figures.

Industry insiders said branch offices in poorer Auckland neighbourhoods suffered worst during the sales slump, and suburbs closer to the city centre fared better.

Ray White Ponsonby branch head Bryce Earwaker said he had not lost any staff during the past year, and he knew of only one sales staff resignation among competitors.

But in Papakura, one realtor's office has shrunk from 30 staff to 10.

Ray White Papakura branch principal Ted Ingram said all staff who left did so for the same reason.

"They can't make any money - sales are down. It's just too tough."

Mr Ingram introduced a sales limit during the recession, and told salespeople who could not meet it that it might be better for them to go into another industry.

"Those who haven't made their businesses more efficient are no longer in business."

The Real Estate Agents Authority, which the Government set up in November 2009, introduced a new licensing system in March last year.

Those who already had licences could keep them at $800 a year, or put them on hold at $85 a year.

A higher standard of qualification to gain a licence was also introduced, meaning people who let their licences lapse face a more difficult test to get back into the industry.

Mr Smith said some people would have kept a realtor's licence even though they were not active in the market.

Others would have taken the opportunity of a lull in sales to go back into education and upskill to a higher qualification, he said.

But the main driving force behind the exodus from the industry was simply the economy.

"There's a combination of factors but I would put it mainly down to the number of sales," Mr Smith said.

He said there were signs of the real estate market recovering, but the number of sales staff was unlikely to grow yet.

The new system introduced a distinction between salespeople and agents. Only agents are allowed to operate an office.

The Real Estate Agents Authority has brought in other changes to the industry, including a more clearly defined educational system and responsibilities for salespeople.

A disciplinary tribunal has publicly adjudicated on a small number of transgressions, including foul rants, alleged thefts and forgeries, and a dispute involving a marriage breakup.

"Each person is more aware of their responsibilities and there's a level of accountabilities that's been introduced," Mr Smith said.

The changes had generally been positive for the industry, he said.

Mr Manch said that those left in the industry would be operating at a higher level of standards and consumer protection.