A BFA can't be amended. There is no mechanism in the Family Law Act for changing part of an agreement and leaving the rest standing, and your agreement says so in terms: it cannot be waived, modified, varied or added to. What you can do, if both of you agree, is end it, either by replacing it with a new agreement or by terminating it outright.
Legal Basis: Section 90J
Section 90J of the Family Law Act deals with ending a BFA, and it allows exactly two routes:
- A new financial agreement that includes a provision terminating the earlier one
- A separate written termination agreement
Note what isn't on that list. There is no "amendment agreement" and no power to vary. A change of one clause means a whole new agreement, with everything that involves.
Key principle: Either route needs a new written agreement that meets all the same formal requirements as the original BFA, including fresh independent legal advice for each of you.
Two Options for Changing a BFA
1. New BFA (Replacing the Old One)
Create an entirely new BFA that terminates and replaces the original. This is the route for any change at all, from a single clause to a complete rethink.
When to use:
- Major life changes (having children, buying a house, starting a business)
- Significant shifts in financial circumstances
- The original BFA is outdated or no longer reflects reality
Requirements:
- All the same requirements as the original BFA:
- Full financial disclosure (updated)
- Independent legal advice (fresh certificates)
- Written document signed by both parties and lawyers
- Must explicitly state it "revokes and replaces" the earlier BFA
Pro tip: Treat this like drafting a BFA from scratch. Update all asset values, disclose new acquisitions, and ensure both parties understand the new terms. The new agreement is governed by whichever of ss. 90B, 90C or 90D fits your circumstances at the time you sign it, which may not be the same section as the original.
2. Termination Agreement (Section 90J)
End the BFA entirely without replacing it.
When to use:
- You no longer want a BFA (e.g., relationship has matured, trust has increased)
- You're separating and prefer to negotiate a settlement without being bound by the BFA
- The BFA is causing disputes and you'd rather start fresh
Requirements:
- Written termination agreement signed by both parties
- Independent legal advice for each party (certificates required)
- Must explicitly state the BFA is "terminated" or "revoked"
Important: Once terminated, the BFA has no effect. If you later separate, you'll be back to standard s. 79 property division (unless you make Consent Orders or a new BFA).
What You Cannot Do
❌ Amend the Existing Agreement
There is no such thing as an amendment to a BFA. You cannot add a clause, change a figure, or annex a variation to the original, however small the change. If something needs to be different, the whole agreement is replaced or terminated.
❌ Informal Changes
You cannot:
- Handwrite amendments on the original BFA
- Agree verbally to ignore certain clauses
- Email each other saying "let's not follow the BFA anymore"
Why? Section 90G requires written agreements with legal advice certificates. Informal changes are not enforceable.
❌ Unilateral Changes
One party cannot end a BFA alone. Both of you must agree and sign, and neither of you can force the other to do it. A clause purporting to let one party terminate on their own doesn't get around section 90J, which sets out the only two ways an agreement ends by consent. (A court setting an agreement aside under s. 90K is a different thing entirely, and is not something either of you controls.)
❌ Backdating
You cannot backdate a new agreement or a termination agreement to make it seem like it was signed earlier. Courts treat backdating as fraud.
The Process: Step-by-Step
Step 1: Identify the Need for Change
Life events that commonly send couples back to their lawyers:
- Having children
- Buying property or starting a business
- Receiving an inheritance
- One party stops working (e.g., to care for children)
- Significant income change
- Relationship breakdown (wanting to terminate the BFA)
Step 2: Full Financial Disclosure (Again)
Update your financial statements to reflect current circumstances:
- New assets acquired
- Changes in asset values (e.g., property appreciation)
- New debts or liabilities
- Updated super balances
Exchange these updated financial statements before negotiating changes.
Step 3: Negotiate New Terms
Work with your partner (and lawyers) to agree on:
- What parts of the BFA need changing
- What the new terms should be
- Whether to replace the BFA with a new one or end it altogether
Step 4: Draft the New Agreement or Termination Agreement
Your lawyer drafts the new agreement, ensuring it:
- Complies with s. 90J
- References the original BFA clearly
- Includes all necessary clauses
- Is clear and unambiguous
Step 5: Independent Legal Advice (Mandatory)
Each party must receive fresh independent legal advice on:
- The effect of the new agreement or termination
- Advantages and disadvantages
Lawyers sign new s. 90G certificates.
Step 6: Sign and Store
Both parties sign the new agreement. Lawyers sign certificates. Keep original copies safe.
Pro tip: Store the new agreement or termination agreement with the original BFA. If you ever need to enforce one or challenge the other, you'll need both documents.
Common Scenarios
Scenario 1: Having Children
Original BFA: Property split 50/50, no provision for children.
New BFA: Replace it with one that specifies:
- Primary carer gets family home
- Super split adjusted to 60/40 in favour of primary carer
- Provision for child-related expenses
Scenario 2: Buying a House Together
Original BFA: Each party retains their pre-existing assets.
New BFA: Replace it with one specifying that the new house is joint property, split 50/50 (or based on contributions).
Scenario 3: One Party Starts a Business
Original BFA: No business interests.
New BFA: Replace it with one quarantining the new business as separate property, protected from property division.
Scenario 4: Separation (Terminating the BFA)
Why: You've separated and the BFA feels unfair now. Both parties agree to terminate it and negotiate a fresh settlement.
Process: Sign a termination agreement, then either negotiate a new BFA or proceed with Consent Orders.
Cost & Timeframe
Through a traditional law firm, you can typically expect:
- New BFA: $2,000–$4,000 (same as creating a BFA from scratch)
- Termination Agreement: $1,000–$2,000
- Timeframe: 2–6 weeks (depending on complexity and negotiation)
The Bottom Line
BFAs are not "set and forget." Life changes, and an agreement written years ago may not suit the life you're living now.
What you can't do is tinker with it. There is no amendment, no annexure, no pen-and-initials change that works. The agreement stands as signed until the two of you replace it or end it, each of which means a fresh agreement with fresh advice on both sides.
Do it that way, or risk finding out the hard way that the change you thought you'd made was never binding at all.
