Postnups - How to Protect Your Newfound Assets During Your Marriage

Family Law: 06 June 2025

Author: Kara Inglese - Our People

You may have heard the buzzword “prenup” amongst pop culture involving high profile celebrities – but have you heard of “postnups”?

Background on Binding Financial Agreements

In Australia, ‘Binding Financial Agreements’ (“BFA”) operate pursuant to the Family Law Act 1975 (Cth) sections 90B, 90C and 90D. BFAs under these sections are used to protect assets and outline clear financial expectations between parties to a marriage, to avoid costly legal disputes surrounding the division of the asset pool in the event of a relationship breakdown. Though some people critique that a BFA may reflect a lack of trust and the beginning of a catastrophic end to a relationship, BFAs are becoming increasingly prevalent in Australia, as couples are acknowledging the importance of being forthright in outlining their financial affairs with their partner openly and honestly. 

BFAs can be established during all stages of a marriage including prior to, during, or after divorce.

Typically, people tend to think of protecting their assets prior to entering a marriage and may in fact neglect to consider protecting those assets that they acquire during a marriage or relationship.

What is a postnup?

Postnuptial agreements under Sections 90C and Section 90D are those legally binding BFAs that aim to protect assets of the parties even after they are married.

This type of BFA may be applicable and beneficial especially where a party wants to protect certain assets or the financial circumstances of individuals within the marriage change such as:

• Where one party receives a substantial inheritance from a deceased estate;
• Where one party acquires a new asset, such as a residential or investment property;
• Where one party is establishing and growing a new business venture;
• Where parties have not yet formalised a prenuptial agreement and would like to satisfy their peace of mind moving forward in the relationship. 

Postnuptial agreements can cover a variety of financial items relevant to a relationship, including:

• assets;
• debts and liabilities;
• income and future anticipated income;
• inheritances;
• wills;
• property division;
• superannuation entitlements;
• insurance; and
• business ownership.

This agreement should outline the division of property and debts upon parties’ separation and/or divorce or encountering an irrecoverable breakdown in their marriage, and the payment of ongoing spousal maintenance and child support if applicable.

Advantages and Disadvantages of a postnup

There are several benefits to implementing postnuptial agreements. Parties can feel secure and assured about their individual and spousal financial affairs, rights and obligations, enjoying a peace of mind whilst continuing their relationship. Further, due to the legally binding nature of postnuptial agreements, individual interests are legally protected, so long as full and frank disclosure of financial affairs was made, and that parties willingly entered into the agreement.  In the event of a bitter unamicable relationship breakdown, a fair division of the asset pool may be difficult to ascertain, requiring dispute resolution or legal proceedings, drawing out the matter and its expenses.

Accordingly, postnuptial agreements are able to prevent expensive, the stress of proceedings, significantly easing the scenario and its associated costs.

Discussions around creating a postnup can be daunting, overwhelming and emotional, and may contribute to friction or strain on a relationship however, they should not always be perceived as a negative thing.

There are of course risks with entering into a Postnuptual agreement and you should obtain legal advice as to whether it is the right step for you and your partner.  It is noted that if one or both parties to a postnup do not obtain independent legal advice prior to executing a postnup, the enforceability of the document can be argued. 

Is a postnup right for you?

It is certainly beneficial for individuals to consider whether a postnuptial agreement would be suitable and appropriate for their personal and spousal circumstances. Postnuptial agreements can provide a practicable, secure, comforting, and clear path for couples moving forward in their relationship, outlining financial affairs and obligations with clarity, rather than looking at binding financial agreements as a bleak outlook into a couples’ future.

Postnup Lawyers in Victoria

If your personal and/or financial circumstances have recently changed, and you think that a postnuptial agreement may be beneficial to protect your assets and ensure a mutual understanding of your financial matters with your spouse, our highly experienced family law team would be happy to assist. 

If you would like some advice or guidance in relation to BFAs, please call our office on (03) 8600 6000.