Marriage vs. Common Law in Ontario: The Definitive Guide to Your Rights
The legal differences that could cost you hundreds of thousands of dollars
Verified Legal Strategy
Legal Strategy reviewed by Deepa Tailor, Senior Family Lawyer. Updated January 2026 to reflect current Family Law Act distinctions.
Too Busy to Read? The 30-Second Comparison:
Property: Married couples have automatic equalization (50/50). Common Law couples have ZERO automatic property rights (what's yours is yours).
The Home: Married spouses cannot be kicked out of the Matrimonial Home. Common Law partners can be evicted if not on the title.
Support: Both types of partners can claim Spousal & Child Support (if criteria are met).
The "I Do" Difference
You bought a house together. You have kids. You've lived together for 10 years. In the eyes of your friends, you are married. In the eyes of the Family Law Act, you are strangers when it comes to property.
This is the most dangerous assumption in Ontario family law: that common law relationships carry the same legal protections as marriage. They don't. Not even close.
The difference between saying "I do" and simply living together can mean the difference between walking away with half the equity in your home or walking away with nothing. Between having a legal right to stay in your house or being locked out overnight.
The Biggest Risk: Property Division
| Legal Issue | Married Couples | Common Law Couples |
|---|---|---|
| Matrimonial Home Rights | Both spouses have equal right to possession, regardless of whose name is on title. Cannot be locked out. | NO automatic right to possession. If not on title, you can be evicted. Must prove Constructive Trust. |
| Pension Division | Automatic equalization of pension value accrued during marriage. Calculated by actuary. | NO automatic right. Must prove Unjust Enrichment and establish Constructive Trust over pension. |
| Equalization Payment | Automatic 50/50 split of net family property (NFP). Spouse with higher NFP pays half the difference. | NO equalization. Each partner keeps what they own. Must litigate for any share. |
| Business Valuation | Business value included in NFP calculation. Spouse entitled to share of increase during marriage. | NO automatic right. Must prove contributions to business and claim Unjust Enrichment. |
The Only Path for Common Law: Unjust Enrichment
If you're common law and want any share of property not in your name, you must prove a legal doctrine called "Unjust Enrichment" and establish a "Constructive Trust" over the asset.
The Three-Part Test:
- 1.Enrichment: Your partner received a benefit (e.g., you paid their mortgage, renovated their house, contributed to their business).
- 2.Deprivation: You suffered a corresponding loss (you spent your savings, gave up career opportunities, provided unpaid labor).
- 3.No Juristic Reason: There is no legal justification for the enrichment (no contract, no gift, no other explanation).
This is expensive, time-consuming litigation. You need bank records, receipts, witness testimony, and expert evidence. Married couples get equalization automatically. Common law couples must fight for every dollar.
The Home: Who Stays?
CRITICAL WARNING FOR COMMON LAW PARTNERS
If you are common law and not on the title, you do not have a "Right to Possession." You can be locked out.
This is not theoretical. We see this happen regularly: one partner changes the locks, and the other partner has no immediate legal remedy. Police will not intervene because it's a "civil matter." You must go to court and prove you have an interest in the property.
Married Spouses
- Both spouses have equal right to live in the matrimonial home
- Cannot be evicted without a court order
- One spouse cannot sell or mortgage the home without the other's consent
- Protection applies even if only one name is on title
Common Law Partners
- NO automatic right to possession if not on title
- Can be locked out and must go to court to gain entry
- Title holder can sell or mortgage without your consent
- Must prove Constructive Trust to claim any ownership interest
Not Married? Document Your Contributions Now.
If you're common law and contributing to property, a business, or your partner's career, you need to create a paper trail today. Download our evidence checklist to protect yourself.
What's Inside:
- Financial contribution tracking template
- Property improvement documentation guide
- Evidence preservation checklist
- Unjust enrichment claim preparation
Support & Kids: The Similarities
Good News: Children Are Treated Equally
The law does not distinguish between children born to married parents and children born to common law parents. Both have the same rights to:
- Child Support: Calculated using the Federal Child Support Guidelines based on the payor's income
- Decision-Making Responsibility: Both parents have equal rights to make major decisions about the child's upbringing
- Parenting Time: Courts apply the "Best Interests of the Child" test equally, regardless of parents' marital status
Spousal Support: The Critical Time Limit
Both married and common law partners can claim spousal support, but there's a crucial difference in timing:
Married Spouses
No time limit to bring a spousal support claim. You can file years after separation (though delay may affect the amount).
Common Law Partners
2-year limitation period from the date of separation. If you don't file within 2 years, you lose the right forever.
Eligibility for Common Law Partners: You must have cohabited for at least 3 years, OR have a child together and a relationship of some permanence.
How to Protect Yourself
Prevention: Cohabitation Agreements
A Cohabitation Agreement is a contract that creates the property rights that don't exist by default for common law couples. It can specify:
- How property will be divided if you separate
- Whether spousal support will be paid (and how much)
- How joint purchases (home, car, investments) will be treated
- Protection for business owners and high earners
Cure: Separation Agreements
If you're already separating, a Separation Agreement can still resolve property, support, and parenting issues without going to court. This is your chance to negotiate a fair settlement before litigation costs spiral.
Key advantage: Both parties can agree to terms that differ from what a court might order, giving you more control over the outcome.
Litigation: Constructive Trust Claims
If negotiation fails, you must litigate. This means proving Unjust Enrichment and establishing a Constructive Trust over the property. You will need:
- Bank statements showing financial contributions
- Receipts for renovations, repairs, or improvements
- Witness testimony about your contributions
- Expert valuation of the property or business
Reality check: This process can take 2-4 years and cost $50,000-$150,000+ in legal fees. Prevention is always cheaper than cure.
Frequently Asked Questions
Does common law become marriage after 7 years?
Can I claim my partner's pension if we're common law?
What is the Matrimonial Home and why does it matter?
Can common law partners get spousal support?
What is a Cohabitation Agreement and do I need one?
What happens to our house if we separate and we're common law?
Don't Guess Your Rights. Know Them.
Whether you're married or common law, understanding your legal position is the first step to protecting yourself. Book a strategy session to get clarity on your specific situation.
Book a Common Law Strategy Session