Prenuptial Agreement: The Real Cost, and Why Nobody Knows How Often They Hold Up

August 24, 2026 3 Min Read

A prenuptial agreement in Australia has a legal name: a Binding Financial Agreement. Most law firm pages avoid stating what it actually costs. Here’s the real price range. Here’s a real gap nobody talks about too.

Quick Answer: Prenuptial Agreement Cost and Reality

In Australia, a prenuptial agreement is called a Binding Financial Agreement, or BFA. A typical BFA costs $10,000 to $20,000 in total. That’s once both parties get their own independent legal advice. A simple agreement without much negotiation can cost less, around $4,000 to $5,000. The other party’s independent advice adds roughly $5,000 more. There’s no official register of BFAs in Australia. Nobody actually knows how many are made. Nobody knows how many get challenged, or how many hold up in court. This isn’t legal advice. Always speak with a family lawyer about your own situation.

What a Prenuptial Agreement Actually Costs

A typical total cost runs $10,000 to $20,000. This covers both parties’ legal advice and the drafting itself.
A straightforward agreement can cost less. Without much negotiation, expect $4,000 to $5,000 for the drafting.
The other party’s independent advice adds roughly $5,000. Both people need their own lawyer. That’s what makes the agreement enforceable.
Most law firm websites avoid stating a number at all. Many push readers toward a paid consultation instead of giving a real range upfront.

The “Black Hole” Nobody Talks About

There’s no official register of Binding Financial Agreements in Australia. Nobody tracks how many are actually made each year.
We don’t know how many get challenged in court. No public data exists on dispute rates.
We don’t know how many actually hold up. There’s no register, so there’s no way to measure success or failure rates.
This is a real transparency gap. Anyone signing a BFA does so without reliable data on how often they work as intended.

What Can Get a Prenup Overturned

Both parties lacking independent legal advice. This is one of the most common ways a BFA becomes unenforceable.
Being signed under duress or undue influence. A court can void an agreement if one party wasn’t genuinely free to say no.
Circumstances changing significantly. A big life change left out of the original agreement can weaken it.
Fraud, or hiding the truth about assets. Hiding assets or giving false financial information can void the agreement entirely.
A technical mistake under the Family Law Act. Even a well-meant agreement can fail if it misses a specific legal step.

Who a Prenup Suits

Anyone with more assets than their partner going in. A BFA can protect what you brought into the relationship.
Business owners who want to protect a company. This keeps a business separate from other shared assets.
People who’ve been through a hard divorce before. A BFA can offer more certainty than a court later.
De facto couples too, not just married ones. BFAs have covered de facto and soon-to-be de facto couples since 2009.

Making a Prenup More Likely to Hold Up

Both people need their own separate lawyer. This is a must, not an option.
Be open about your finances. Hiding assets is one of the clearest ways to get an agreement challenged later.
Avoid signing under time pressure. An agreement rushed right before a wedding date can look like it was signed under duress.
Check it every few years. A BFA that skips big life changes is easier to challenge and win against.

FAQ: Prenuptial Agreement

What is a prenuptial agreement called in Australia?
A Binding Financial Agreement, or BFA. It functions like a prenup but is the correct legal term used here.

How much does a prenuptial agreement cost in Australia?
Typically $10,000 to $20,000 in total. A straightforward agreement can cost less, around $4,000 to $5,000, plus roughly $5,000 for the other party’s independent legal advice.

Can a prenuptial agreement be overturned?
Yes. Common reasons include no independent legal advice, duress, a big change in circumstances, fraud, or a technical mistake under the Family Law Act.

Is there data on how many prenups get challenged in court?
No. There’s no official register of Binding Financial Agreements in Australia. That means there’s no reliable data on how often they’re disputed or upheld.

Do both people need their own lawyer for a prenup?
Yes. Independent legal advice for both parties is required for the agreement to be enforceable.