United StatesBinding Financial Agreement

Australian Binding Financial Agreements (Pre-Nup): Key Rules

Last updated: 8 April 2026 · BeforeYouSign Editorial Team

Australia does not call them pre-nups, but Binding Financial Agreements (BFAs) entered into before marriage under s 90B of the Family Law Act 1975 (Cth) serve the same purpose: setting out how assets will be divided if the relationship breaks down. BFAs are notoriously fragile. They can be set aside for a long list of reasons — non-disclosure, duress, unconscionable conduct, failure to get proper independent legal advice, and subsequent 'material change in circumstances'. Before signing, make sure the formalities are watertight.

What is a Pre-nuptial BFA Requirements?

A Binding Financial Agreement (BFA) is a contract between spouses or de facto partners under Parts VIIIA or VIIIAB of the Family Law Act 1975 (Cth) that deals with property and maintenance matters. A pre-nuptial BFA is made under s 90B, with de facto equivalents under s 90UB.

Red flags to watch for

Only one party has independent legal advice

Section 90G requires each party to have had independent legal advice about the effect of the agreement and its advantages and disadvantages. Without it, the BFA is not binding.

Agreement signed under time pressure shortly before the wedding

Courts have set BFAs aside for duress where a party had insufficient time to consider the agreement before committing to marriage. The leading case, Thorne v Kennedy [2017] HCA 49, is highly relevant.

Incomplete financial disclosure

Material non-disclosure is a ground for setting aside the BFA under s 90K(1)(a) (fraud).

No sunset or review clause for material changes

A BFA that ignores future children, health changes, or career shifts is more vulnerable to being set aside under s 90K(1)(d) (change in circumstances making it impracticable).

Legal advice certificates not attached to the agreement

Section 90G(1)(b)(ii) requires each party to receive a signed statement from their lawyer confirming advice was given. These statements must be attached to the BFA.

Clause attempting to oust the Family Court's jurisdiction

A BFA ousts the court's general property adjustment powers, but attempting to block the court's power to set aside the BFA under s 90K is void.

Your legal rights

Parts VIIIA (married) and VIIIAB (de facto) of the Family Law Act 1975 (Cth) govern BFAs. Section 90G sets the strict formal requirements for binding status. Section 90K lists the grounds on which a BFA may be set aside, including fraud, duress, non-disclosure, and material change of circumstances. Thorne v Kennedy [2017] HCA 49 is the leading case on unconscionable conduct. Only a court can set a BFA aside.

Questions to ask before you sign

  • 1Have we both received independent legal advice from different lawyers, with signed certificates?
  • 2Has each party made full and complete financial disclosure in a schedule?
  • 3Is there a review or sunset clause in the event of major life changes?
  • 4Does the agreement comply with s 90G formalities for binding status?
  • 5What is the procedure if either of us becomes financially incapacitated?
  • 6Have we considered how Thorne v Kennedy affects the timing of signing before the wedding?

Disclaimer: This guide is for educational purposes only and does not constitute legal advice. Contract law varies by jurisdiction and individual circumstances. Always consult a qualified legal professional before making decisions based on this information.

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