Real estate agents are predicting a rush of investment properties to hit the market over the coming weeks as investors nearing retirement sell off properties to take advantage of new superannuation legislation.

The short window of opportunity allows people to contribute up to $1 million in after tax dollars to their super between May 10 and June 30.

After this date, individuals will only be able to contribute up to $150,000 a year. Sales consultants say they are fielding a lot of inquiries from clients looking to sell.

Tony Pagano of CB Richard Ellis Milton, said he had had three clients who had sold with the intention of topping up their superannuation.

"To some people it is worthwhile," he said. "There were three or four properties I was marketing late last year which all sold which were in part or totally motivated by this."

Mr Pagano said those who chose to sell would be "selling their property in the best market ever".

Brad Johnston from Colliers International on the Gold Coast said investors aged 55 and over had found the offer particularly attractive.

"If your 50 then you would be better off gearing your property," he said.

Mr Johnston also has three clients on the books at the moment looking to sell properties to put the money into their super. He said the shake up was proving to be the biggest reshuffle in investment properties in years.

"There will be a flutter of investment properties to come on the market over the next few weeks," Mr Johnston said.

Superannuation expert Paul Banister, from Grant Thornton, said those who own properties that had experienced large capital gains and were subject to capital gains tax had found the offer less attractive.

"Those people who are able to get out of investments quite easily might find it to be good, but those with a hefty capital gains bill might find it’s a much harder decision," he said.

"Typically, it’s for those nearing the age when they can no longer put money into super.

"For those many years out (from retirement), the cost of letting an opportunity like this go past is greatly reduced."

Mr Banister said he had numerous clients with large residential and commercial property portfolios looking to take advantage of the offer over the next few months.