You have built something worth protecting. A home deposit, a small business, an inheritance from a grandparent or simply years of careful saving. Now you are moving in with your partner or planning a wedding, and a question sits at the back of your mind: What happens to all of this if the relationship does not last?
Asking that question does not mean you expect to fail. It means you are thinking clearly about your future. In Australia, the tool people reach for is a prenuptial agreement, even though that is not the name the law gives it. And the numbers show why so many couples now consider one. The Australian Bureau of Statistics recorded 47,216 divorces in 2024 and the marriages behind them lasted a median of just over 13 years.
This article explains what a prenuptial agreement in Australia actually is, whether it holds up in court, how de facto couples fit in, why the do it yourself route is risky and what the process looks like when you do it properly.
What a prenuptial agreement means in Australia
In American films, couples sign a “prenup”. Australia does not use that term in law. Here, the correct name is a Binding Financial Agreement, often shortened to a BFA.
A Binding Financial Agreement is a written contract between two people that sets out how their property, assets, superannuation and debts will be divided if the relationship ends. It is governed by the Family Law Act 1975 for married and de facto couples across most of the country.
A BFA does not have to be signed before the wedding. You can enter into one:
- Before you marry or move in together (the classic “prenup”)
- During the marriage or de facto relationship
- After separation, to formalise a settlement
So the label “prenuptial” only describes the timing. The legal instrument is the same either way.
A well drafted agreement can cover the property and savings you each bring in, superannuation, how future income or an inheritance is treated, business interests and how any joint debts are handled. The real value is certainty. Instead of leaving it to a future court, you decide now, together, while things are calm.
Why couples consider a prenuptial agreement
A prenup is not only for the wealthy. If you are bringing any of the following into a relationship, an agreement is worth speaking with a family lawyer about:
- A property or a deposit you have saved on your own
- A business, company or family trust
- An inheritance you have received or expect to receive
- Children from a previous relationship and assets you want to preserve for them
- Significant debt held by one partner that the other does not want to inherit
Talking openly about money before you commit tends to strengthen a relationship rather than strain it. You go in knowing where you both stand.
Is a prenuptial agreement valid in Australia?
Yes. A prenuptial agreement is legally binding in Australia provided it is in writing, both parties received independent legal advice from separate lawyers, and each lawyer signed a certificate confirming that advice was given. Skip any of those steps and a court can find the agreement is not binding.
To be binding, a Financial Agreement must meet strict technical requirements set out in the Family Law Act (section 90G for married couples and section 90UJ for de facto couples). Simply, all of the following must happen:
- The agreement is in writing and signed by both parties.
- Before signing, each person receives independent legal advice from their own lawyer about how the agreement affects their rights and about the advantages and disadvantages of signing it.
- Each lawyer provides a signed statement, sometimes called a Solicitor’s Certificate, confirming that advice was given.
- A copy of that statement is given to the other party.
- The agreement has not been terminated or set aside by a court.
The second requirement is the one people overlook. The two of you cannot use the same lawyer. Your interests may conflict, so the law requires each party to have separate, independent advice. An agreement where both relied on one solicitor is exposed to challenge from the start.
Full financial disclosure is the other pillar. Both parties must lay their finances on the table honestly. If one person hides an asset or a debt, the agreement can later be unwound for non disclosure. The courts take these requirements seriously.
Do de facto couples need a prenuptial agreement in Australia?
Many couples assume these rules only apply to marriage. They do not. Under the Family Law Act, de facto partners, including same sex couples, have broadly the same property and financial rights and obligations as married couples.
A de facto prenuptial agreement in Australia works the same way as one for a married couple. You enter into it before, during or after the relationship, and it must meet the same requirements to be binding.
Timing matters here. If a de facto relationship breaks down, there is a two year window from the date of separation to apply to a court for a property settlement or spousal maintenance. For married couples, the limit is 12 months from the date the divorce is finalised. A BFA lets you settle the financial question on your own terms rather than relying on those court timeframes.
If you want to understand your position on either front, our pages on property settlements and spousal maintenance walk through the basics, and our separation and divorce page covers the broader process.
Prenuptial agreements in Western Australia are different
Western Australia is the one part of the country that plays by its own rulebook for de facto couples.
If you are getting married, the federal Family Law Act 1975 applies to you even in WA, the same as everywhere else. If you are in a de facto relationship in Western Australia, your agreement is governed by separate state legislation, the Family Court Act 1997 (WA), not the federal Act.
The practical effect is similar. A prenuptial agreement in Western Australia still requires independent legal advice and a signed certificate from each party’s lawyer. The requirements simply sit in a different Act. A WA family lawyer will make sure yours is drafted under the correct one, because getting that wrong can make the agreement ineffective.
The risks of a DIY prenuptial agreement in Australia
Search “prenuptial agreement template Australia” and you will find plenty of downloadable kits promising a legal agreement for a small fee. It is tempting. It is also where a lot of people come unstuck.
A do it yourself prenuptial agreement in Australia is not binding on its own, no matter how good the template looks. The template is only paper until each party has received proper independent legal advice and been given a signed certificate to that effect. Skip that step and a court can set the agreement aside, which usually surfaces at the worst possible moment, years later, when the relationship has already broken down.
The problems with a DIY prenuptial agreement tend to be:
- No independent legal advice, so the agreement fails the binding test straight away
- Vague or contradictory wording that a court finds uncertain and unenforceable
- Incomplete financial disclosure, opening the door to a challenge for non disclosure
- Clauses that try to deal with things a BFA cannot validly cover
The irony is that a badly prepared agreement can cost far more than a proper one. A dispute over a flawed BFA can end up in litigation and legal fees that dwarf what a lawyer would have charged to get it right. A template gives you a document, not protection.
What does a prenuptial agreement cost, and how do you get one?
Every situation is different, and cost depends on how complex your finances are. As a general guide, straightforward agreements often start at a few thousand dollars per person, while matters involving a business, a trust or a larger asset pool can run higher. Each party needs their own lawyer, so there are two sets of fees to plan for.
Weighed against the alternative, a BFA is closer to an insurance policy. A contested property settlement through the courts can cost tens of thousands of dollars and take a year or more to resolve.
The process itself is more direct than most people expect: you speak with a family lawyer, both parties disclose their finances honestly, the terms are negotiated, one lawyer drafts the agreement and the other party takes it to their own solicitor for independent advice.
Give yourself time. An agreement signed under pressure days before a wedding is far more vulnerable to challenge, a point the High Court has made plainly. For a clear breakdown of costs and next steps based on your specific circumstances, get in touch with our team or call 1300 110 080.
Can a prenuptial agreement be overturned in Australia?
Yes, a court can set aside a prenuptial agreement, but only on limited grounds. A BFA is difficult to overturn when it has been prepared properly, which is exactly why preparation matters so much.
Under the Family Law Act, a court may set aside a Financial Agreement where:
- It was obtained by fraud, including a failure to disclose a material asset or debt
- One party behaved unconscionably, or there was undue pressure or a serious imbalance of power
- The agreement is uncertain or impractical to carry out
- Circumstances relating to a child have changed in a way that would cause hardship
The leading case is Thorne v Kennedy [2017] HCA 49. There, an agreement signed shortly before a wedding, under significant pressure and with a large disparity in bargaining power, was set aside by the High Court even though it appeared properly executed. The lesson is not that BFAs are fragile. It is that they must be entered into freely, with genuine advice on both sides and without last minute pressure. Get that right and the agreement holds.
If a dispute over an agreement does arise, having experienced family lawyers who understand court and mediation options on your side makes a real difference.
Frequently asked questions
Is a prenuptial agreement legally binding in Australia?
Yes, provided it is in writing, both parties received independent legal advice from separate lawyers and each lawyer signed a certificate confirming that advice. Without those steps, a court can find the agreement is not binding.
Are binding financial agreements enforceable?
Yes, provided they meet the Family Law Act requirements: written, independently advised on both sides, fully disclosed and free of fraud or undue pressure. An agreement missing any of these can be challenged or set aside.
Can you write your own prenuptial agreement in Australia?
You can write a draft, but a do it yourself or template agreement is not binding on its own. It only becomes enforceable once each party has received independent legal advice and been given a signed certificate. This is why a lawyer is required, not optional.
What if my partner has proposed a Binding Financial Agreement for me to sign?
You are entitled, and legally required, to get your own independent legal advice before you sign anything your partner or their lawyer has drafted. A lawyer acting for you alone will explain what the agreement actually means for your position, weigh up its advantages and disadvantages and, if it does not reflect your interests, negotiate changes on your behalf. Signing a proposed agreement without this step is one of the fastest ways it can later be challenged, since a court can find it was never binding to begin with.
Do de facto couples need a prenuptial agreement?
De facto couples have similar property rights to married couples under the Family Law Act. A de facto agreement is not compulsory, but it is worth considering if either partner has assets, a business, an inheritance or children from a previous relationship to protect.
Are prenuptial agreements valid in Western Australia?
Yes. Married couples in WA are covered by the federal Family Law Act. De facto couples in WA are covered by the Family Court Act 1997 (WA) instead, so a WA agreement should be drafted under the correct legislation.
When should you sign a prenuptial agreement before a wedding?
As early as you reasonably can. An agreement signed under time pressure days before the ceremony is far more open to challenge. Starting the process several months out gives both parties time to take advice and reflect.
How much does a prenuptial agreement cost in Australia?
A simple agreement often starts in the low thousands per person, while complex matters involving businesses or trusts can reach $10,000 or more. Each party needs their own lawyer, so there are two sets of fees.
Getting a prenuptial agreement right, from the start
A prenuptial agreement is one of the most practical financial decisions a couple can make. Done properly, it gives you both clarity and control. Done as a DIY afterthought, it can fall apart when you need it most.
The difference comes down to getting the right advice early. At Allen Evans Family Lawyers, we prepare and review Binding Financial Agreements for couples across every kind of relationship, and we explain the process simply so you always know where you stand.
If you are thinking about a Binding Financial Agreement, we would be glad to talk it through with you. Call us on 1300 110 080 or make a free enquiry online to arrange a confidential, no pressure conversation about your circumstances.
This article is intended as general information only and does not constitute legal advice. For advice specific to your circumstances, contact Allen Evans Family Lawyers on 1300 110 080 or via our enquiry form.