Introduction
Buying a home with someone you're not married to, whether a friend, a sibling, a parent, or a romantic partner, is more common than it used to be. Rising home prices, stagnant wage growth, and the increasing financial difficulty of buying solo have pushed more buyers toward co-ownership as a practical path into homeownership.
Done well, co-buying can make an otherwise unaffordable purchase possible, distribute the costs and responsibilities of ownership across two or more people, and build equity for everyone involved. Done poorly, it can damage relationships, create legal complications, and leave people trapped in a property they can't easily exit.
The difference between those two outcomes comes down almost entirely to how thoroughly the arrangement is planned before anyone signs anything.
Why People Co-Buy
The financial motivations are usually straightforward. Co-buying allows two or more buyers to pool their down payments, qualify for a larger loan using combined incomes, share the monthly mortgage and carrying costs, and access homeownership in markets where individual incomes aren't sufficient.
For buyers who are priced out individually, co-buying can be the difference between owning and renting indefinitely. In expensive coastal markets especially, it's an increasingly common solution for people who want the financial benefits of ownership but can't get there alone.
The Legal Structure: How You Hold Title
One of the first and most important decisions in a co-buying arrangement is how you take title to the property. This determines what happens if one co-owner dies, wants to sell their share, or can no longer contribute to the mortgage.
Tenancy in Common
Each co-owner holds a defined percentage share of the property. Shares don't have to be equal: one person might own 60% and another 40%, reflecting their respective contributions. Each owner can sell or transfer their share independently, and when an owner dies, their share passes to their heirs (not automatically to the co-owner). This is the most flexible structure and the most commonly used for co-buyers who aren't married to each other.
Joint Tenancy with Right of Survivorship
Each co-owner holds an equal share. If one owner dies, their share automatically passes to the surviving co-owner(s), bypassing probate. This is common among married couples but less suited to friends or family members who may have other intended heirs. It also requires equal ownership percentages, which may not reflect unequal financial contributions.
Community Property
Only available in community property states (Arizona, California, Idaho, Louisiana, Nevada, New Mexico, Texas, Washington, Wisconsin) and only applicable to married couples. Not relevant for most friend or family co-buying arrangements.
For most non-married co-buyers, tenancy in common is the appropriate structure. Consult a real estate attorney in your state before deciding, as state-specific rules apply.
The Co-Ownership Agreement: The Most Important Document You'll Sign
The purchase contract and the mortgage paperwork are required documents. The co-ownership agreement is an optional document that most co-buyers don't create, and it's the single biggest source of problems when co-buying arrangements go wrong.
A co-ownership agreement (sometimes called a co-tenancy agreement or co-habitation agreement) is a private legal contract between the co-buyers that spells out how the arrangement works. It should cover:
Ownership Percentages
Who owns what percentage, and how was that determined? If one person contributed more to the down payment, does that translate to a higher ownership percentage? If contributions were equal, shares are presumably equal.
Mortgage Contributions
Who pays how much of the monthly mortgage, taxes, insurance, and other carrying costs? Are contributions equal or proportional to ownership percentages? What happens if one person can't make their payment in a given month?
Maintenance and Repairs
How are maintenance costs divided? Who decides when a repair is necessary and how to handle it? Is there a spending threshold above which both parties must agree before work is authorized?
Decision-Making
How are major decisions made? What requires unanimous agreement versus majority? What happens if co-owners can't agree on something significant?
Exit Provisions
This is the most critical section. What happens when one co-owner wants to sell their share? Does the other co-owner have the right of first refusal to buy it? How is the buyout price determined? What happens if neither co-owner can afford to buy out the other? What process governs a full sale of the property?
Death or Incapacity
What happens to a co-owner's share if they die? If they become incapacitated and can no longer contribute? How is this coordinated with each co-owner's estate planning?
Default
What are the remedies if one co-owner stops paying their share of the mortgage or carrying costs? What notice is required? What options does the non-defaulting co-owner have?
This agreement should be drafted by a real estate attorney, not downloaded from the internet. The legal and financial stakes are too significant for a generic template. Budget $500 to $1,500 for the agreement as part of your transaction costs.
Mortgage Considerations for Co-Buyers
When multiple buyers apply for a mortgage together, all co-borrowers' incomes, assets, and credit histories are considered. This has both advantages and risks.
The advantage is qualification power: combined income allows you to qualify for a larger loan than either borrower could obtain individually. The risk is that all co-borrowers are jointly and severally liable for the entire mortgage. If one person stops paying, the lender comes after all borrowers. Your credit is affected by the other person's payment behavior, and vice versa.
It's also possible for one person to be on the mortgage and both on the title, or both on the mortgage and both on the title, or various other combinations. Each arrangement has different financial and legal implications. Talk through the options with your lender and attorney to understand what structure makes sense for your specific situation.
The Conversations You Need to Have Before You Buy
Legal documents matter, but so does actually talking through the scenarios before they happen. Some of the most important conversations to have with your co-buyer before signing anything:
- What does each of us expect this arrangement to look like in five years? In ten?
- What happens if one of us wants to move out before the other?
- What happens if one of us gets married or has children?
- What if one of us loses their job or has a financial hardship?
- How do we make decisions when we disagree?
- How do we handle it if we want to sell and the market isn't favorable?
- Are we both equally committed to maintaining the property?
These conversations are uncomfortable precisely because the scenarios feel unlikely. But the value of having them before you're legally bound together is enormous. Discovering that you have fundamentally incompatible expectations is much better done before closing than after.
When Co-Buying Works Well
Co-buying arrangements tend to succeed when both parties are financially stable and contributing reliably, expectations are aligned and explicitly documented, there's a clear and fair exit path that both parties understand, both co-owners have compatible living standards and decision-making styles, and the relationship is strong enough to handle the occasional friction that comes with shared property ownership.
When Co-Buying Goes Wrong
The most common failure modes: one co-owner's financial situation changes and they can no longer contribute, a relationship break (romantic, friendship, or family) makes the arrangement untenable, co-owners disagree on a major decision and have no resolution mechanism, one co-owner wants to exit and there's no clear process for how to do that, or the property needs to be sold at a loss and both parties have to absorb more than they expected.
None of these are reasons not to co-buy. They're reasons to plan for them explicitly in your agreement before they happen.
Final Thoughts
Co-buying is a legitimate and increasingly common path into homeownership. It works when it's approached as the serious legal and financial arrangement it is, with written agreements, clear expectations, honest conversations, and professional legal guidance.
The relationship you're co-buying with matters enormously. Co-buying with someone you trust, who is financially responsible, and with whom you can have direct conversations about difficult topics is fundamentally different from doing it with someone where any of those things is in question.
Get the agreement. Have the conversations. And if you're not comfortable doing both, that's probably a signal about the arrangement worth listening to.
Sources & Further Reading
For authoritative information on the topics covered in this article, consult these resources:
