How to Protect Your Inheritance From a Spouse or Common-Law Partner in Canada

In Canada, inheritances are excluded from family property division by default — but that exclusion is fragile. The moment inherited funds are deposited into a joint account, used for shared expenses, or paid toward the family home, the exclusion disappears and the funds become shareable. Protection requires deliberate steps: keeping the inheritance separate, documenting its origins, and for most people, a marriage contract or cohabitation agreement that makes the exclusion explicit and durable.

How inheritance is treated under Canadian family law — the default rule

The starting point is actually favourable. Under Ontario's Family Law Act R.S.O. 1990, c. F.3, inheritances and gifts received from a third party after the date of marriage are excluded from net family property. Only assets accumulated during the marriage are generally shareable — pre-marriage property, gifts, and inheritances are deductible from the equalization calculation.

The same principle applies across most Canadian provinces. In BC under the Family Law Act SBC 2011, inheritances are classified as "excluded property." In Alberta under the Family Property Act, gifts and inheritances are generally exempt. The specific rules and terminology differ, but the baseline intent is consistent: inherited money is yours, not the relationship's.

The problem is what happens after you receive it.

The commingling trap — how inherited money becomes shareable

Commingling is the process by which clearly separate inherited funds become indistinguishable from marital assets — and therefore shareable at separation. It's the most common and most costly inheritance planning failure.

Depositing into a joint account. The moment inherited funds land in a joint account, the exclusion is at risk. Courts look at tracing — whether the inherited funds can be tracked from their origin to their current form. Once mixed with contributions from both partners, tracing becomes difficult or impossible. What can't be traced is treated as shared.

Using inherited funds toward the matrimonial home. This is the most severe version of the commingling trap in Ontario, and the one with the least remedy. Under FLA s. 4(1), a home that becomes the matrimonial home cannot have pre-marital equity deducted. If you use a $200,000 inheritance as a down payment on the family home, that $200,000 doesn't get credited back to you at separation — the entire equity of the home enters equalization. The inheritance exclusion doesn't apply to the matrimonial home.

Using inherited funds for shared expenses. Paying joint bills, renovations, or shared purchases from an inherited account gradually erodes the paper trail. Courts expect clear documentation of the inheritance and what happened to it.

Income earned on inherited funds. In Ontario, the exclusion covers the inheritance itself — but income earned on inherited funds (investment returns, rent) is shareable unless a will clause or marriage contract specifically states that income is also excluded. This distinction matters significantly over the life of a long marriage.

The five-step protection framework

Step 1: Keep it in a separate account in your name only. Open a dedicated investment or bank account solely in your name and deposit the inheritance directly from the estate. Never deposit it into a joint account. If inherited funds need to move for any reason, document every transfer with clear records linking the movement back to the estate.

Step 2: Don't use it for the matrimonial home. In Ontario, using inherited funds toward the family home converts them into unprotectable equity. If you want to use an inheritance to help buy a home with your spouse, get legal advice first — a marriage contract can define how your contribution is credited at separation, even though the matrimonial home exception limits what's possible. But the cleanest protection is not using the inheritance for the family home at all.

Step 3: Document everything. Keep the will, letters from the estate executor, bank statements showing the original deposit, and records of any subsequent movement of the funds. If you later invest the inheritance, keep the investment account statements showing the connection between the original deposit and the current holdings. Courts require tracing — the documentation is the tracing.

Step 4: Be deliberate about income. Inheritance income (dividends, rental income, investment returns) is shareable by default in Ontario unless the will or a marriage contract specifies otherwise. If you're investing a substantial inheritance, get the treatment of income addressed explicitly in a marriage contract.

Step 5: Get a marriage contract or cohabitation agreement with explicit anti-commingling provisions. The steps above are operational protection. A marriage contract is legal protection. See the next section.

Why a marriage contract or cohabitation agreement does what operational steps alone can't

Operational steps — keeping the account separate, maintaining records — protect you if you follow them perfectly, for the entire life of the relationship, and if nothing changes. A marriage contract protects you even if circumstances evolve.

A marriage contract can include:

Explicit inheritance exclusion. "Any inheritance received by Spouse A during the marriage, and any growth or income on those funds, shall remain Spouse A's separate property and shall be excluded from net family property." This removes the ambiguity about income and growth that the default rule creates.

Anti-commingling provisions. "The exclusion in the preceding paragraph shall not be affected by the co-mingling of inherited funds with other assets, or by the use of inherited funds for household expenses, provided that Spouse A maintains reasonable documentation of the origin of the funds." This is the clause that keeps the exclusion intact even if the operational steps aren't followed perfectly.

Treatment of inherited funds used for joint purposes. If inherited money goes toward a renovation, a vehicle, or a jointly-used asset, the contract can define whether that's treated as a non-refundable gift to the household or a contribution that's credited back at separation. Without this clause, the answer is determined by litigation.

Protection of future inheritances. "Any inheritance received by Spouse A before or after the date of this agreement shall remain Spouse A's separate property." Courts will generally respect clearly drafted future inheritance clauses in agreements that were otherwise well-made with full disclosure and ILA.

For common-law couples, a cohabitation agreement accomplishes the same thing. Common-law partners in Ontario have no automatic property rights at separation — but the unjust enrichment risk means that if an inheritance is used in ways that benefit the relationship, a claim may still arise. A cohabitation agreement with explicit inheritance protection and anti-commingling provisions provides a juristic reason that defeats unjust enrichment claims before they arise.

For the full picture on what a marriage contract covers under Ontario's Family Law Act — including all the asset classes that can be addressed and how — that article covers the legal framework. For common-law property rights in Ontario and why a cohabitation agreement matters for unmarried couples specifically, that article covers the unjust enrichment framework in detail.

What parents can do — family law clauses in wills

If you're receiving an inheritance rather than protecting one, ask your parents about including family law protection clauses in their will. This is a legitimate and underused estate planning tool.

Under Ontario's Family Law Act, a will can include a clause stating that the inheritance and any income or growth on it is intended to remain the exclusive property of the child recipient, excluded from any equalization claim by their spouse. For this exclusion to extend to income and growth — not just the inheritance principal — the will must specifically say so. The general exclusion covers the original amount; the income exclusion requires explicit wording.

Key requirements:

• The will must have been made or updated after 1986 when Ontario's Family Law Act was passed
• The clause must specifically address income and growth if those are to be excluded, not just the principal
• The protection offered by the will clause is strongest when combined with the recipient's own operational steps and marriage contract — the will clause alone doesn't protect against commingling

For parents gifting a down payment rather than leaving an inheritance: document the gift clearly with a gift letter establishing it's non-repayable and intended for the child alone. Encourage the child to have a marriage contract or cohabitation agreement that specifically addresses how the down payment contribution is treated if the relationship ends. A gift letter creates evidence of intent; a marriage contract creates a legal framework that holds up at separation.

The matrimonial home exception — the gap no will clause can close

One limitation no amount of planning fully resolves in Ontario: the matrimonial home exception.

Under FLA s. 4(1), a home that becomes the matrimonial home cannot have pre-marital equity deducted in the equalization calculation — even if the home was purchased entirely with inherited funds. A $400,000 inheritance used to buy a family home doesn't create a $400,000 exclusion at separation. The full equity enters equalization.

A marriage contract can partially address this — by defining the inherited contribution as a credit that offsets equalization, or by establishing a custom sharing formula for the home's equity — but it cannot fully replicate the treatment that inherited funds would receive if they were kept separate and invested rather than used for the family home.

The practical planning implication: if you receive a substantial inheritance and are considering using it toward a family home, get legal advice before doing so. The question isn't whether you can protect it — it's how much protection is achievable and what structure gives you the best outcome.

How this differs for common-law couples

For married couples in Ontario, inherited funds are excluded from net family property by default, subject to the commingling and matrimonial home exceptions above.

For common-law couples in Ontario, the Family Law Act's equalization provisions don't apply — there's no automatic property sharing. But common-law partners may still make unjust enrichment claims if they contributed to property that benefited from the inheritance. The protection against these claims is a cohabitation agreement, not the default rules.

For common-law partners' inheritance rights at death: in Ontario, a common-law partner has no automatic inheritance right if their partner dies without a will. The estate passes under intestacy rules to children, parents, or siblings — not to the surviving partner. Common-law partners need a will, beneficiary designations on RRSPs and TFSAs, and joint ownership structures to protect each other at death.

BC is meaningfully different. Since 2013, common-law couples in BC have near-equal property rights after two years of cohabitation. Inheritances are generally classified as excluded property under BC's Family Law Act — but BC has also confirmed that inheritances retain their excluded status even when transferred to joint accounts (though growth remains shareable). BC common-law partners also have automatic inheritance rights at death if they meet the threshold. If you've recently moved from BC to Ontario, your legal situation has changed materially.

Frequently Asked Questions

Is my spouse automatically entitled to my inheritance in Canada?

No — not in most provinces. Under Ontario's Family Law Act, inheritances received after the date of marriage are excluded from net family property by default. Your spouse has no automatic entitlement to the inheritance principal. However, this exclusion is fragile: it's lost if inherited funds are commingled with joint assets, used for the matrimonial home, or if the inheritance generates income that isn't separately addressed. A marriage contract with explicit anti-commingling provisions is the most reliable protection.

Is my common-law partner entitled to my inheritance in Ontario?

No — not automatically. Ontario's equalization regime applies only to married spouses. Common-law partners have no automatic right to share in an inheritance. However, if inherited funds were used in ways that benefited the relationship — funding a shared home, supporting shared living expenses — an unjust enrichment claim may still arise. A cohabitation agreement with explicit inheritance protection provides the most reliable defence against such claims.

What happens if I deposit an inheritance into our joint account?

The exclusion is at serious risk. Courts require tracing — demonstrating that inherited funds can be tracked from their origin to their current form. Once funds are deposited into a joint account and mingled with contributions from both partners, tracing becomes difficult or impossible. What can't be traced is treated as shared property. Keep inherited funds in a separate account in your name only.

Can I use an inheritance as a down payment on our family home?

You can — but in Ontario, you lose the inheritance exclusion for those funds. Under FLA s. 4(1), the matrimonial home cannot have pre-marital or pre-contribution equity deducted from equalization, regardless of source. A marriage contract can partially address this by defining your contribution as a credit, but it cannot fully replicate the protection that separate, invested inheritance funds would receive. Get legal advice before using an inheritance toward the family home.

Can my parents protect my inheritance through their will?

Yes — through a family law clause. In Ontario, a will can specify that an inheritance and any income or growth on it is intended to remain the child's exclusive property, excluded from any equalization claim by their spouse. Income and growth are excluded only if the will explicitly says so — the general exclusion covers the principal. This clause is most effective when combined with the recipient's own operational steps (separate account, documentation) and a marriage contract.

Does this work differently in BC?

Yes, meaningfully. In BC under the Family Law Act SBC 2011, inheritances are classified as excluded property and BC has confirmed they retain that status even when transferred to joint accounts — though growth during the relationship remains family property. BC common-law partners also have near-equal property rights after two years and automatic inheritance rights at death if they meet the threshold. Ontario's rules are stricter: separate accounts, no matrimonial home exclusion, and no automatic common-law partner inheritance rights.

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This article provides general information about Canadian family law and does not constitute legal advice. Laws vary by province. For advice specific to your situation, consult a licensed family lawyer in your province.