Exchange of Contracts: When a Property Deal Becomes Binding

“Exchange” is the usual NSW description for the step that creates a property contract, but Australia does not use one formation process. In some jurisdictions the practical question is whether both parties have signed the same contract and acceptance has been communicated. Your solicitor or conveyancer should confirm the exact formation time from the document, signatures, delivery record and local law.

What exchange means

In the NSW counterpart process, buyer and seller sign matching copies and those signed copies are exchanged. The NSW Governmentdescribes exchange as the legally binding step and says it is commonly arranged electronically by the parties' solicitors, conveyancers or agent.

That is not a safe national definition. The legal effect may instead turn on acceptance of an offer, both signatures on one document, notification to the buyer, or rules in the approved contract. Use “contract formation” as the broader question and “exchange” only where it accurately describes the transaction.

How formation differs by jurisdiction

• NSW: the official guide describes two signed copies being swapped. Before that step, the agreement is usually not binding; after it, the contract and any cooling-off or conditions govern.
• Victoria: Consumer Affairs Victoria says a private-sale property is sold when both buyer and seller have signed the contract. It separately says an eligible buyer's cooling-off period begins from the date the buyer signs.
• Queensland: the Queensland Government contract guide says the contract becomes binding when buyer and seller have signed it. It tells buyers to obtain independent legal advice before signing and to ensure negotiated conditions are written into the contract.
• Western Australia: WA Consumer Protection describes the Offer and Acceptance process, including counter-offers and conditional offers. There is no mandatory cooling-off period, so the accepted terms matter immediately.
• South Australia: SA.GOV.AU says the seller is legally bound once seller and buyer sign, while an eligible buyer may still have the separate statutory cooling-off period.
• Northern Territory: NT.GOV.AU says an offer is not accepted by the seller until the contract for sale is signed. The approved contract and how it came into force then determine the next steps.

ACT and Tasmanian transactions also have their own documents and formation rules. A local adviser should confirm the position rather than importing terminology from another state.

What to confirm before signing

What to confirm after formation

Ask your adviser for a written critical-dates list drawn from the final signed contract. It may include deposit, cooling-off, finance, inspection, disclosure, settlement and notice dates. Do not rely on a “standard” 30-, 42- or 60-day timeline: the agreed date and contract wording control.

Also confirm when the contract allocates risk, when insurance should begin, who holds the deposit, what searches remain, and how amendments must be documented. These points differ by jurisdiction and contract.

If you need to withdraw

A cooling-off right, finance condition, inspection condition, disclosure remedy and default are different legal paths with different tests and notice requirements. Do not send a DIY cancellation. Follow the urgent checklist in pulling out after signing a property contract and obtain transaction-specific advice.

General information only, not legal advice. Reviewed 24 August 2026. Property contract formation and remedies depend on the jurisdiction, the document and the facts; obtain advice before signing.