The NSW Budget will effectively price many first homebuyers out of the market, a top broker has said.

Under the newly-released budget, the NSW Government's stamp duty exemption will only apply to first-time buyers purchasing a newly constructed home. The change, set to come into effect from January 1, will see buyers looking to purchase an established dwelling slapped with more than $20,000 in stamp duty for a home valued at $600,000.

MPA Top 100 Broker Justin Doobov has told Australian BrokerNews the move will knock many potential buyers out of the market.

"It's definitely going to price first home buyers out of the market as they now need to save another 5% to cover stamp duty. This is going to cause a large hole in the market as there will be a lag as new buyers will have to save the extra money needed," Doobov commented.

Raine & Horne chief executive Angus Raine agrees, and commented that many young buyers looking for inner city units will now have to defer their purchases, and will subsequently put additional strain on infrastructure in Sydney's outer suburbs.

"I'd really urge the NSW Government to reconsider this budget measure as it will mean first timers will need to find tens of thousands of additional dollars to buy into the housing dream," Raine said.

The residential construction industry, however, has praised the move, with HIA executive director for NSW David Bare calling it a "positive step" to stimulate the home building sector.

Regardless of how the policy impacts first homebuyers, Doobov said investors could find a window of opportunity in the changes.

"There will be a good opportunity for investors to jump in the market once the exemption is removed as there will be a lag in the market pricing while the buyers adjust to the new requirements," he said.