Buying a home as an unmarried couple in Quebec 2026: co-ownership agreement and legal protection

In Quebec, more than 40% of couples live in common-law unions. Yet, unlike married couples, common-law partners have no automatic protection on jointly acquired property. Buying a home without signing an indivision agreement exposes both partners to major financial and legal risks on separation. For the divided vs undivided co-ownership angle, see our divided vs undivided co-ownership guide. This article covers the essential agreement for unmarried couples.

The legal gap for common-law partners in Quebec

The Quebec Civil Code does not recognize the unmarried couple as an automatic legal unit. Family patrimony (article 414 and following), which shares equally the value of the family home, furniture, vehicles, and pension plans, applies only to married or civil-union couples.

Consequence: a common-law couple buying a property together buys in undivided co-ownership under the Code's general rules (articles 1010 and following). No automatic rule on shares, on buyout at separation, on the treatment of mortgage payments made solely by one partner, or on renovations financed by one alone.

The indivision agreement resolves these grey zones in advance. It is a notarial contract, enforceable against third parties, that defines who owns what, who pays what, who can buy out, and under what rules.

The 6 essential clauses of an indivision agreement

Clause 1 — Indivision shares. Defines each partner's share (default 50-50, or other depending on actual down payment). Registered to title. Determines how proceeds are split on sale and fiscal responsibilities (capital gains proportional to shares).

Clause 2 — Financial contributions. Details initial down payment, monthly mortgage payments, municipal taxes, condo fees, and renovations. Avoids disputes over "who paid how much".

Clause 3 — Buyout right on separation. Defines who can buy out the other partner's share, under what terms (independent appraisal, market price, payment deadline). Avoids forced sale and litigation.

Clause 4 — Right of first refusal on third-party sale. If a partner wants to sell their share to someone else, the other partner has purchase priority at the same terms. Prevents an unwanted third-party co-owner.

Clause 5 — Treatment on death. The agreement can provide a heirs' buyout right or direct transfer to the surviving partner. Must be combined with a will (without a will, the deceased's share goes to legal heirs: parents or children, never the common-law partner).

Clause 6 — Conflict resolution mechanism. Mandatory mediation before litigation, arbitration, or independent expert valuation clause. Drastically reduces costs in case of disagreement.

Unequal down payment: how to structure shares

Classic case: Partner A puts $50,000 down, Partner B puts $20,000. Joint mortgage $380,000. Several structures possible:

Option 1 — Strict proportional shares. A gets 60% share, B gets 40%. Reflects the down payment. Suitable if future payments are also unequal (based on income).

Option 2 — 50-50 shares with personal receivable. A and B are 50-50 co-owners, but A has a $30,000 personal receivable repayable on sale or separation. Suitable if A and B want equal decision-making and responsibility.

Option 3 — Progressive buyout. B gradually buys A's share through monthly payments to reach 50-50. Suitable if B's income is higher and they want to balance ownership over time.

Taxation and succession: pitfalls specific to common-law partners

Principal residence exemption: each partner can designate their share as a principal residence and benefit from the capital gains exemption. Plan carefully against other properties (cottage, rental condo) each partner owns.

Death without a will: the deceased's share goes to legal heirs under the Civil Code. For a childless common-law partner, parents and siblings inherit — not the surviving partner. The survivor may end up co-owning with in-laws or siblings-in-law. Must absolutely be avoided via a notarial will.

Death with a will: the survivor can inherit the share. But without a prior indivision agreement, transfer terms and capital gains calculation become complex. The agreement + will form the minimum protective pair.

Common mistakes by unmarried couples

Mistake 1 — "We will sort it out later". Purchase happens without an agreement. When separation comes 5 years later, cold-blooded negotiation is impossible. Major emotional and financial cost.

Mistake 2 — "We will sign after the purchase". Possible but costlier (separate notarial deed after acquisition). Better: sign the agreement alongside the deed of acquisition at the same notary.

Mistake 3 — Confusing common-law and marriage. The Quebec legislator explicitly chose not to extend family patrimony to common-law partners. Living together for 20 years grants no automatic right on the other's property.

Mistake 4 — Registering the property in one partner's name only. "To simplify the mortgage". Consequence: the other partner has no rights to the property, even after 30 years of shared payments. Catastrophic on separation or death.

Hamza Taleb, OACIQ broker at RE/MAX (438 877-8525), works with a network of notaries specialized in Quebec real estate law. Professional referral to properly structure your common-law purchase, with indivision agreement and tailored will.

Conclusion: $1,500 to avoid $30,000

An indivision agreement costs $700 to $1,500 at the notary. A partition lawsuit at the Superior Court can exceed $15,000 to $30,000 per partner, on top of the emotional cost. The economic case is settled. Combined with a will, the agreement is the minimum protection for any unmarried couple buying a property in Quebec in 2026.