Buying a house with your partner or associates: the risks of co-ownership

Buying a house with your partner or business partners is common, but it creates a co-ownership with a risk that almost no one explains to you: none of the owners are obliged to remain in it. Any co-owner can demand at any time that the house be divided and, if it cannot be physically divided, that it be sold and the money divided, without the consent of the others. Furthermore, each co-owner can sell or mortgage your percentage buying them separately, and buying them 50/50 opens the door to a simple disagreement being resolved by a judge.

This is one of the most frequent questions we receive at City Laws: people buying a home with their partner, sibling, or business partner assume that "sharing the house" is simply a matter of trust. It's also a matter of law. Below, we explain, using the Civil Code, what co-ownership is, its real risks, how to limit them, and what additional costs apply when one owner is a foreigner and the house is located on the Quintana Roo coast.

What is co-ownership (and what exactly are you buying)

The Federal Civil Code is clear in its article 938: “there is co-ownership when a thing or a right belongs jointly to several persons.” That expression, undivided, That's the key. When you buy a house with another person, you don't become the owner of a bedroom or "your" square footage, but of a aliquot —a percentage— of the ENTIRE property. If they buy 50/50, they both own 100% of the house, 50% each; nothing is physically divided, and that's the root of the problems that come later. That's why it's advisable that a real estate lawyer Please state in writing who contributes how much and what percentage remains in each person's name in the deed.

The main risk: no one is obligated to stay

This point surprises almost everyone. Article 939 states that those who own a thing “cannot be compelled to keep it undivided.” In simpler terms: As a general rule, any co-owner can request, whenever they want, that the co-ownership be terminated.. If your partner or business associate has a falling out with you or needs the money, they have the right to demand the division of jointly owned property. This rule has exceptions, which Article 939 itself recognizes: division cannot be requested when the property is indivisible by its nature or when the law mandates indivision; furthermore, co-owners can agree among themselves to keep the property undivided for a temporary period (agreement of indivision).

Joint ownership isn't a lock: it's a door that any of the owners can open at any time. And if the house can't be divided up, the solution is to sell it and split the money.

Since a house cannot usually be physically divided without destroying its value, in practice it is sold and the proceeds divided according to the agreed-upon percentages; Article 976 confirms that co-ownership ceases, among other reasons, upon the division or sale of the jointly owned property. It doesn't matter if you don't want to sell: if the other party demands it through legal channels, the process moves forward.

Risk of paralysis: why 50/50 can become a trap

Buying in equal shares sounds fair, but it has a legal flaw. Decisions regarding the management of the house—renting it out, major repairs—are made by the owners. most and they bind everyone, even those who voted against it (art. 946). And article 947 clarifies that this majority is twofold: “the majority of co-owners and the majority of interests”, that is, a majority of people AND a majority of percentage.

What happens when there are two owners of a 50%? There is never a possible majority, And the law doesn't provide an automatic tie-breaker. Article 948 resolves it in an awkward way: "If there is no majority, the judge, after hearing the interested parties, will decide what should be done within the framework proposed by them." In other words: a disagreement can end up being decided by a judge. That's why the 50/50 rule, so intuitive, is the one that most easily gets stuck.

Anyone can sell or mortgage their share without permission

Another risk that few see coming: you don't control what the other person does with their share. Article 950 recognizes that "every co-owner has full ownership of their corresponding share," and can to sell it, transfer it, or mortgage it without asking your permission. However, according to the second clause of Article 950, the effect of that sale or mortgage on the other co-owners is limited to the portion allocated to them upon termination of the co-ownership: the third party does not become the owner of specific square meters or bedrooms, but rather of the share. It may happen that one day you wake up as a co-owner with a stranger—who bought the other's share—or with their mortgage holder. The law provides protection against the sale of that share to a stranger: the right of first refusal. Note: this protection does not apply to mortgages; according to Article 950, the co-owner can freely mortgage their share, without giving you preference.

The protection that the law gives you: the right of first refusal

Article 973 establishes the right of first refusalBefore selling their share to a stranger, the co-owner must notify the others—either through a notary or judicially—of the agreed-upon sale, so that within the eight days Those who bid after the offer may match it and purchase the sale with priority. The penalty is clear: according to the same article, “until notification has been made, the sale will have no legal effect.” And if several co-owners wish to exercise their right of first refusal simultaneously, Article 974 gives preference to the one representing the largest share; if the shares are equal, the decision is made by lottery, unless otherwise agreed.

Unmarried couple: contributing money is not the same as being the owner

There's an expensive misunderstanding here. Buy together Being unmarried does not automatically create a community of property.. The house is governed by co-ownership rules, and each person owns only the percentage that appears in their name on the writing. If someone contributes money but their share isn't recorded in the deed—or their percentage is less than what they contributed—they don't acquire ownership simply by making payments. At the federal level, cohabitation doesn't automatically create a joint ownership arrangement; the person who contributed but didn't receive title would have to pursue other legal avenues, proving their contributions. That's why the best protection is simple: that the writing reflects the real percentages.

Married couple: first define your property regime

If they are married, the first question is under what marital property regime. Article 178 of the Federal Civil Code establishes that marriage is celebrated under marital partnership or separation of assets, And that regime defines what happens to the house:

• Marital partnership: The property may become part of the common estate, governed by the terms of the marriage contract (art. 183).
• Separation of assets: Each spouse retains their own property (arts. 207-218), and a joint purchase behaves like ordinary co-ownership, with all the risks already described.

The arrangement is agreed upon in a prenuptial agreement and defines from the beginning the fate of the house if the marriage ends.

Quintana Roo Note: Foreign owner and house on the coast

If you shop in Cancun, Playa del Carmen or Tulum with a partner or associate foreign, In addition, there is the constitutional restriction. Article 27, section I, prohibits foreigners from acquiring direct ownership of real estate within the restricted area, defined by the Foreign Investment Law as the strip of 100 kilometers along the borders and 50 kilometers along the beaches. Almost the entire coastline of Quintana Roo falls within it.

For a foreigner to have the use and enjoyment of a residential house in that area, the procedure is the trust with a Mexican credit institution as trustee, subject to prior authorization from the Ministry of Foreign Affairs (Article 11 of the Foreign Investment Law); it cannot have direct ownership. This trust lasts a maximum of 50 years, renewable (art. 13). If the purchase is made through a legal entity, a Mexican company with a clause excluding foreigners can directly acquire housing in a restricted zone, and without that clause, for non-residential purposes by notifying the SRE (art. 10). In Quintana Roo, co-ownership is also governed by its own state Civil Code, which replicates the federal scheme. If your case involves co-ownership, a foreign owner, and a property on the coast, the most prudent course of action is book legal advice before signing.

How to reduce risks before buying

Co-ownership isn't inherently bad; the problem is moving in without rules. Basic precautions:

1. Write down the actual percentages in writing; don't leave it to "we understand each other".
2. Avoid, if you can, a pure 50/50 split between two: It is the one that is most easily paralyzed.
3. Agree on rules of administration and exit. in a co-owners agreement: how it is decided and how someone who wants to leave sells their share.
4. With a foreign owner on the coast, structure the purchase from the beginning (trust or partnership).

Frequently Asked Questions

If I buy a house with my partner, does each of us own a part of the house?

Not exactly. Under co-ownership (Article 938 of the Federal Civil Code), both own a percentage—a fractional share—of the entire house, not a specific room or square footage. Nothing is physically divided: both own the entire property, in the proportion established by the deed.

Can my business partner or spouse force me to sell the house?

You can demand the termination of the co-ownership. Article 939 states that no one is obligated to remain in undivided ownership, so any co-owner can request its division; and if the house cannot be physically divided, the solution is usually to sell it and split the proceeds. Your consent is not required to initiate the process.

Can my co-owner sell their share without notifying me?

Article 950 allows you to sell or mortgage your share. However, if you are going to sell to a third party, Article 973 requires you to be notified by a notary or through the courts so that you have eight days to match the offer (right of first refusal). Until this notification is made, the sale has no legal effect.

I put down the money but the house is in my partner's name, am I the owner?

If you're not married, ownership is defined by the deed, not by who paid. Contributing money doesn't automatically make you the owner if you're not listed as the titleholder; your claim would have to be pursued through other channels, proving your contributions. That's why it's important that the deed reflects the actual ownership percentages.

With a foreign partner on the coast of Quintana Roo, is it possible to buy?

Yes, but not under direct foreign ownership. In the restricted zone (50 km of beach), the route is a bank trust with permission from the Ministry of Foreign Affairs (Article 11 of the Foreign Investment Law), for up to 50 years, renewable, or a Mexican company.

Legal notice

This content is for informational purposes only and provides an overview of the general framework for co-ownership and real estate purchases in Mexico. It does not constitute legal advice for a specific case, does not create an attorney-client relationship, and does not guarantee any outcome. The Civil Code, the Foreign Investment Law, state regulations, and court rulings may change and be applied differently depending on the transaction, and local regulations vary from state to state. Before signing any documents or handing over any money, consult an attorney about your specific situation.

⚠️ General informational content, current as of its publication date. It is not legal advice and does not create an attorney-client relationship; laws change and every case is different. For your specific situation, Book a free consultation.