Common-Law Separation & the Matrimonial Home in Alberta

One of the most common misconceptions in Canadian separation law is that common-law couples don't have the same property rights as married couples. In Alberta as of January 2020, that's not true anymore. The Family Property Act was amended to extend matrimonial property rights to "adult interdependent partners" — the legal term Alberta uses for what most people call common-law. Once you meet the qualifying threshold, your separation goes through essentially the same property division rules as a marriage.

This article covers what adult interdependent partnership actually means in Alberta, how property division works, and how the spousal buyout mortgage program treats common-law separations. The mortgage rules are unambiguous: common-law qualifies. The legal mechanics around getting there are worth understanding clearly.

Adult Interdependent Partners — Alberta's Common-Law Definition

Alberta's Adult Interdependent Relationships Act (AIRA) was passed in 2003 and uses the term "adult interdependent partner" instead of "common-law spouse." The terminology is awkward but legally precise. To qualify as adult interdependent partners, two people must have lived together in a relationship of interdependence and meet at least one of these criteria:

• Three years of continuous cohabitation, OR
• Cohabitation of any duration if there is a child of the relationship (biological or adopted), OR
• Entry into an Adult Interdependent Partner Agreement — a written agreement signed by both parties confirming their adult interdependent relationship status

"Relationship of interdependence" is defined as a relationship outside marriage where two people share one another's lives, are emotionally committed, and function as an economic and domestic unit. Roommates and platonic cohabitants don't qualify. Romantic partners sharing a household and finances do.

The three-year clock runs from the start of cohabitation in a relationship of interdependence — not from when you met, dated, or got engaged. The day you moved in together as committed partners is the date that matters.

What Property Rights Common-Law Partners Have

Until January 2020, Alberta's Matrimonial Property Act only applied to legally married spouses. Common-law partners had to rely on common-law remedies (constructive trust, unjust enrichment) to claim a share of property — a slower, more uncertain process.

The 2020 amendments renamed the Act to the Family Property Act and extended its scope to include qualifying adult interdependent partners. The result: separating common-law couples in Alberta who meet the AIRA threshold now have property division rights essentially equivalent to married spouses.

This means:

• The matrimonial home (or family home) is treated as joint property, regardless of whose name is on title
• Property acquired during the relationship is presumptively divided equally
• Property brought into the relationship is generally separate, with appreciation during the relationship potentially shared
• Either partner can apply for property division on separation

The mechanics of the division — what's joint, what's separate, what's exempt, what equalization is owed — are functionally the same as for married couples in Alberta. The same separation agreement template, the same legal process, the same financial outcomes.

What the Family Home Means in a Common-Law Context

Under the Family Property Act, the family home (formerly "matrimonial home") is a specifically protected category of property. Both partners have rights of possession during the relationship and a presumptive equal interest on separation, regardless of whose name is on title.

This matters in common-law cases because the home is often in only one partner's name. Pre-2020, the partner whose name wasn't on title had limited claims. Post-2020, that partner has a presumptive 50% share if the home was acquired during the relationship.

In a buyout scenario, this works the same as in marriage: the partner staying in the home buys out the departing partner's share through a refinance. The buyout amount is calculated using the same formula (see our equity payout calculation guide), and the spousal buyout mortgage program funds it with the same 95% LTV ceiling.

How Lenders Verify Common-Law Status

For the spousal buyout program to apply, the lender needs evidence that the relationship qualified as a spousal relationship. CMHC, Sagen, and Canada Guaranty all accept common-law and adult interdependent relationships, but they want documentation. Acceptable evidence typically includes:

• The separation agreement itself stating the parties were in an adult interdependent relationship in Alberta
• An Adult Interdependent Partner Agreement if one was signed during the relationship (rare in practice)
• CRA documentation — joint tax filings declaring common-law status, or each partner's prior years' returns showing common-law marital status
• Length of cohabitation documented through joint utility bills, joint bank accounts, joint mortgage applications, or other records
• Children of the relationship — birth certificates demonstrate this immediately

The cleanest evidence is a separation agreement that explicitly recites the parties' adult interdependent relationship and the date of separation. Family law lawyers know to include this. If your draft doesn't, ask for it to be added.

Where Married and Common-Law Separations Differ in Practice

While the property division rules are now substantially the same, three practical differences remain:

1. There's no divorce process. Married couples need to obtain a divorce judgment from the Court of King's Bench (formerly Queen's Bench). Common-law partners simply separate — there's no parallel "divorce" decree, because there was no marriage to dissolve. This often makes common-law separation faster legally; you go straight from cohabitation to separation agreement without the year of separation typically required before divorce.

2. Spousal support rules are similar but separate. Married spouses can claim spousal support under the federal Divorce Act; adult interdependent partners claim partner support under the provincial Family Law Act. The amounts and durations are usually similar, but the legal pathways are different.

3. Pension division can be different. Some pension regimes treat married spouses and adult interdependent partners differently for survivor benefits or division on separation. This is technical territory; ask your family law lawyer to address it specifically if you have meaningful pension assets.

Mortgage-wise, none of these differences affect the spousal buyout. The lender treats both files the same.

What If You Don't Quite Meet the Threshold?

The classic borderline case: cohabitation of 28 months, no children, no signed agreement. Under AIRA, this falls short of the 3-year threshold by 8 months. Three options:

Option A: Wait until the threshold is reached. If both partners are willing and the relationship hasn't yet ended legally, simply waiting until the 3-year mark passes triggers the property regime. Practical only if both partners agree on the timing.

Option B: Sign an Adult Interdependent Partner Agreement. A signed AIPA can establish the relationship status earlier than the default 3 years. Rare in practice (most couples don't think to sign one until separation is imminent), but legally valid.

Option C: Pursue common-law remedies. Claims of constructive trust or unjust enrichment exist under common law for relationships that don't qualify under AIRA. These claims can succeed but are more uncertain, slower, and more expensive than statutory matrimonial property division. A family law lawyer assesses fit case-by-case.

For mortgage purposes, the spousal buyout program requires a qualifying relationship. If the relationship doesn't qualify under AIRA, the buyout has to fund as a standard refinance (capped at 80% LTV, no premium-eligible 95% LTV). The 15 percentage point difference in LTV ceiling matters; if your case is borderline, the legal classification has real financial consequences.

The Tax Side: CRA Status and Common-Law

The CRA defines common-law for tax purposes slightly differently than Alberta defines adult interdependent partnership. CRA recognizes common-law after 12 months of cohabitation (or sooner with a child of the relationship). Tax filers must declare common-law status to CRA once it applies.

This matters in two ways for separation files:

• Prior years' tax returns showing common-law status confirm the relationship existed for the period claimed
• Post-separation tax filings should reflect the new single status; CRA expects to see this updated

If you and your former partner filed as common-law for tax purposes for several years and now separate, lenders use those tax filings as part of the documentation that the relationship qualified for the spousal buyout program.

Worked Example: Common-Law Buyout in Cochrane

Consider Anna and Liam, who lived together in a Cochrane home for 4 years, with one child together. Home appraised at $545,000. Existing mortgage $230,000. They've agreed Anna stays with the child, and Liam will be paid out his share.

Relationship status: Adult interdependent partners — qualified by both 4-year cohabitation and the child of the relationship. The Family Property Act applies.

Equity calculation:

• Home value $545,000 minus mortgage $230,000 = $315,000 equity
• Liam's 50% share = $157,500

Buyout structure:

• New mortgage required = $230,000 + $157,500 = $387,500 on $545,000 home = 71% LTV
• Standard refinance fits — sub-80% LTV. No spousal buyout program premium needed
• Anna qualifies on her income plus child support from Liam
• Cleanly documented separation agreement reciting the parties' adult interdependent relationship and the property division

The lender treats this file identically to a married-couple file. The fact that Anna and Liam were never legally married is invisible to the underwriting once the relationship status is documented in the agreement.

The Bigger Picture for Common-Law Separations

The 2020 amendments closed a long-standing gap in Alberta law. Common-law partners who built lives and built homes together now have property rights that protect both partners on separation, including the right to fund a buyout through the federal spousal buyout program.

The practical implications: common-law separating couples in Alberta should approach their mortgage and property division with the same seriousness as married couples. Family law advice. Independent Legal Advice on the agreement. Mortgage broker engagement before the agreement is locked. None of this is overkill in common-law cases anymore — the property stakes are substantively the same.

For more on the broader mechanics of how the spousal buyout works once relationship status is established, see our walkthrough of how a spousal buyout mortgage works in Alberta. For agreement-specific requirements, see our separation agreement requirements guide.

If you're separating from a common-law partner in Alberta and need to fund a buyout, call (403) 404-0048 or visit the spousal buyout mortgage service page.

Frequently Asked Questions

Do common-law partners have property rights in Alberta?

Yes — since January 2020, the Family Property Act extends matrimonial property rights to qualifying adult interdependent partners.

How long does cohabitation need to last?

3 years by default, less if there is a child of the relationship, less if a signed Adult Interdependent Partner Agreement exists.

Can common-law partners use the spousal buyout program?

Yes — CMHC, Sagen, and Canada Guaranty all extend the program to qualifying adult interdependent relationships.

Published: April 27, 2026. Alberta family law and federal mortgage rules change. Consult your family law lawyer and a mortgage broker for your specific situation.