NSW property purchase: when does the contract become binding?

In NSW, the sale generally becomes legally binding when contracts are exchanged. Before exchange, the buyer or seller can usually still change their mind. NSW Government recommends getting the contract reviewed by a solicitor or licensed conveyancer before exchange because the contract sets the terms of the sale and important property information. Official source: NSW Government contracts and deposits when buying property. Guide: https://getinstantlaw.com/property-buying-selling/contract-problem