Bank of Mum and Dad Contract: 2026 Guide

By The Chipkie Team, Personal Finance Editorial Team  ·  Last updated 5 July 2026

Australian parents are now the ninth-largest “lender” in the country by mortgage volume, with Digital Finance Analytics estimating that parental contributions backed around $36 billion in home purchases in a single year. Yet the vast majority of those transfers happen without any written agreement at all. If your family is about to lend — or gift — money toward a deposit, having a proper bank of mum and dad contract in place isn’t optional. It’s the one thing that protects every relationship and every dollar involved.

A parental loan without agreement is one of the most common causes of family financial disputes in Australia. When property values shift, relationships break down, or a parent needs aged-care funding, the absence of clear terms can turn generosity into a legal nightmare. This guide explains what a contract should cover in 2025, why it matters legally and financially, and how to put one together without spending thousands on solicitors.

Key Takeaways

• Without a written contract, family loans risk being reclassified as gifts — making the money unrecoverable in disputes, divorce proceedings, or estate claims.
• The ATO may scrutinise undocumented family mortgage help, especially if loan terms don’t reflect arm’s-length conditions or if interest is charged without being declared as income.
• A valid family loan agreement should specify the principal amount, repayment schedule, interest rate (or explicitly state zero interest), default consequences, and what happens if the child’s relationship breaks down.
• Lenders (including banks approving the mortgage) increasingly require a statutory declaration or formal agreement confirming whether parental funds are a loan or a gift.
• A well-drafted contract protects parents’ retirement savings, preserves Centrelink entitlements, and gives adult children clear expectations — strengthening, not straining, the relationship.

Why does a family loan need a written contract in Australia?

A written contract converts a vague family arrangement into a legally enforceable agreement. Without one, Australian courts — including the Family Court — regularly treat parental contributions as gifts, meaning parents cannot recover the funds if circumstances change. A written agreement also satisfies mortgage lenders, the ATO, and Centrelink, each of which treats undocumented family transfers differently and often unfavourably.

The consequences of skipping documentation are concrete:

• Family Court treatment: In property settlements following a separation, the court assesses the “nature” of third-party contributions. If there is no loan agreement, the contribution is almost always treated as a gift to the couple — not a debt owed back to the parents.
• Centrelink asset-testing: According to Services Australia, if a parent “gifts” more than $10,000 in a single financial year (or $30,000 over five years), the excess continues to be counted as a deemed financial asset for up to five years. A properly documented loan is not classified as a gift for these purposes.
• ATO obligations: If you charge interest on a family loan, that interest is assessable income. The Australian Taxation Office can also apply Part IVA anti-avoidance provisions to arrangements that are structured primarily for a tax benefit without genuine commercial substance.
• Estate disputes: Siblings who didn’t receive an equivalent benefit may challenge the estate under family provision legislation in any state or territory, arguing the loan was actually an early inheritance distribution.

We consistently see this mistake across the agreements our users create: families assume goodwill is enough. It is — until it isn’t.

What should a bank of mum and dad contract actually include?

A comprehensive contract should cover at least ten essential terms: loan amount, repayment structure, interest, security, default provisions, relationship breakdown clauses, early repayment rights, dispute resolution, interaction with any mortgage, and signatures from all parties. Missing even one of these creates ambiguity that courts exploit.

Here’s a breakdown of the critical clauses:

1. Loan amount and purpose: State the exact dollar figure and what it’s for (e.g., “deposit contribution for purchase of [property address]”).
2. Interest rate: Specify the rate, or explicitly state 0%. If you’re unsure what’s fair, our guide on setting a fair interest rate for a family loan walks through current benchmarks.
3. Repayment schedule: Monthly, quarterly, or lump-sum upon sale? Include exact dates or triggering events.
4. Security (if any): A caveat on the property title, a second mortgage, or unsecured? Note that most primary mortgage lenders will not permit a second mortgage, so a caveat is the more realistic option.
5. Default provisions: What happens if repayments are missed? Grace periods, late fees, acceleration of the full balance — spell it out.
6. Relationship breakdown clause: If the borrower separates from a partner, does the loan become immediately repayable? This is arguably the most important clause for protecting family funds.
7. Early repayment: Can the borrower repay early without penalty? Usually yes — but state it.
8. Death or incapacity: Does the loan form part of the parent’s estate? Does it offset the borrower’s inheritance share?
9. Dispute resolution: Mediation before litigation saves money and relationships.
10. Signatures and witnesses: All parties sign, ideally with an independent witness. A statutory declaration adds further weight.

For a deeper dive into the risks of proceeding without these terms, see our article on the pros and cons of using the bank of mum and dad.

How do mortgage lenders treat family deposit contributions?

Most Australian banks require borrowers to declare the source of their deposit. If any portion comes from family, the lender will typically require either a signed gift letter (confirming no repayment obligation) or evidence of a formal loan — which they then factor into the borrower’s debt-to-income ratio. Undisclosed family deposit loan risks include mortgage fraud allegations and loan default.

Key lender requirements to be aware of:

• Gift vs. loan distinction: If parents sign a gift letter but privately expect repayment, this is potentially misleading conduct. If the lender later discovers the arrangement, it may constitute a breach of the mortgage contract.
• Serviceability impact: Under responsible lending obligations set out in the National Consumer Credit Protection Act 2009, lenders must verify that borrowers can service all debts — including family loans. A $100,000 parental loan at even modest repayment terms can reduce a borrower’s capacity by hundreds of thousands of dollars.
• Genuine savings test: Some lenders require 5% of the purchase price to come from “genuine savings” — money accumulated over at least three months. Family funds typically do not qualify, meaning the borrower may still need to demonstrate independent savings.

The practical takeaway: decide early whether the contribution is genuinely a gift or a loan, document it accordingly, and be completely transparent with the mortgage lender. Mixing the two creates legal and financial exposure for everyone.

What happens if there’s no contract and things go wrong?

Without a contract, parents face an uphill battle to recover funds. Courts require clear evidence — bank transfers alone rarely prove loan terms. In family law proceedings, undocumented contributions are typically pooled into the couple’s asset base. In estate disputes, siblings may argue the payment was an advancement on inheritance, reducing the borrower-child’s share and creating lasting family conflict.

Consider these real-world scenarios:

• Separation: Your child’s partner claims the $150,000 deposit was a gift to “the couple.” Without a written agreement, the Family Court has no basis to treat it as a debt. The partner walks away with half.
• Aged care: A parent needs residential aged care. The refundable accommodation deposit (RAD) — often $300,000 to $700,000 — must be funded. The money lent to a child is locked in a property with no mechanism to recall it.
• Death of a parent: The lending parent dies intestate or with a will that doesn’t reference the loan. Siblings discover the payment and dispute the estate distribution, arguing they were disadvantaged.
• Tax audit: The ATO queries unexplained large transfers. Without documentation, the parent cannot demonstrate the nature of the transaction, potentially triggering further investigation.

Our experience working with borrowers and lenders shows that families who document their arrangement upfront almost never end up in dispute. Those who don’t document it are disproportionately represented in court filings and complaints to bodies like the Australian Financial Complaints Authority.

How do you actually create a bank of mum and dad contract?

You have three main options: engage a solicitor ($1,500–$3,000+), use a DIY template (risky if it doesn’t cover Australian-specific requirements), or use a purpose-built platform like Chipkie that generates legally structured agreements tailored to family lending. The best option depends on the loan size, complexity, and whether security over property is involved.

Steps to get started:

1. Have the conversation first: Sit down as a family and agree on the basic terms — amount, repayment expectations, whether interest applies, and what happens if circumstances change.
2. Choose your documentation method: For loans under $50,000 without security, a well-drafted agreement may suffice. For larger amounts or where a caveat is involved, legal advice is strongly recommended.
3. Record everything: Transfer funds electronically (never cash) with a clear reference like “Loan — [child’s name] — deposit.” Keep copies of all communications.
4. Review periodically: Circumstances change. Build in an annual review date to confirm both parties are comfortable with the terms.
5. Notify relevant parties: Ensure the mortgage broker, lender, accountant, and — ideally — other family members are aware of the arrangement’s existence (even if not the specific terms).

If you want to understand whether a self-drafted document has legal standing, our guide on whether a self-written contract holds up in court is worth reading before you proceed.

Can you charge interest on a family loan in Australia?

Yes, you can charge interest on a family loan. However, the interest received is assessable income and must be declared to the ATO. If you charge interest at or above the RBA cash rate, ensure the arrangement has genuine commercial substance. Charging no interest is also perfectly valid — just state it explicitly in the contract to avoid ambiguity.

Does a family loan agreement need to be witnessed or notarised?

Australian contract law does not require family loan agreements to be witnessed or notarised to be enforceable. However, having an independent witness sign the document significantly strengthens its evidentiary weight in any dispute. For loans involving property caveats, witnessing requirements may apply under state or territory land title legislation.

Will a family loan affect my child’s borrowing capacity?

Yes. If the contribution is structured as a loan (not a gift), mortgage lenders will include the repayment obligation when stress-testing your child’s debt-to-income ratio. According to ASIC’s MoneySmart, lenders assess all existing debts when determining how much someone can borrow. A $200,000 family loan could reduce mortgage borrowing capacity by a similar or greater amount.

What if the family contribution is genuinely a gift, not a loan?

If the money is a genuine gift with no expectation of repayment, document that too. A signed gift declaration protects both parties — parents can’t later claim it was a loan, and children can’t be pursued for repayment. Remember the Centrelink gifting thresholds: gifts above $10,000 per financial year (or $30,000 over five rolling years) are still deemed as assets for pension purposes.

Whether you’re lending $20,000 for a deposit top-up or $500,000 to help your child buy their first home, a proper contract is the kindest thing you can do for your family. It removes ambiguity, protects everyone’s financial position, and — most importantly — keeps the relationship intact when life throws curveballs. Chipkie helps Australian families create clear, legally structured loan agreements in minutes, without the cost of a solicitor. Start your agreement today and protect what matters most.

Disclaimer: The information provided in this article is for general informational purposes only and does not constitute financial, legal, or tax advice. Australian laws and lending criteria vary by state and territory and may change. Always consult a licensed financial adviser, solicitor, or conveyancer before entering into any financial arrangement or property purchase with another party.