How Does Splitting Equity Work When You Buy a House With Someone Else?
Two names on a mortgage application is the easy part. Figuring out who actually owns what — especially when one person put down more cash upfront, or one income covers more of the monthly payment — is the conversation that tends to get skipped until it suddenly matters.
In short
Equity is generally split according to how ownership is documented on the title, not automatically 50/50 just because two names are on the loan. Buyers can structure ownership as equal shares or as a percentage that reflects unequal down payments, and many people put a separate written agreement in place to track contributions over time. Without that documentation, state default rules typically decide how ownership is treated, which may not match what either person actually intended.
How ownership percentage usually gets set
- Title determines the legal split, not the mortgage. The mortgage is simply an obligation to repay a lender; the deed or title document is what actually establishes who owns what share of the property.
- Joint tenancy usually means equal shares. This structure treats both owners as holding an identical interest, regardless of how much each person contributed financially.
- Tenancy in common allows unequal shares. This structure lets co-owners hold different percentages — say, 65/35 — that can reflect different down payment amounts or ongoing contributions.
Tracking a down payment that wasn’t split evenly
When one buyer contributes significantly more toward the down payment, that difference is often reflected either in the ownership percentage itself or through a separate reimbursement arrangement if the property is later sold. Some buyers formalize this with a co-ownership agreement outside the deed, spelling out whether the unequal contribution should be repaid before equity is split, versus simply baked into a higher ownership percentage from the start.
What happens to equity as the mortgage gets paid down
Equity grows over time both from paying down principal and from any increase in the home’s value. If both owners contribute equally to the mortgage payment going forward, tracking additional equity is usually straightforward. It gets more complicated when contributions diverge after the purchase — one person covering more of the mortgage, or paying for major improvements — since without an agreement specifying how that’s treated, it can be unclear whether that extra contribution changes the ownership split or is simply treated as a gift to the household. This is part of why figuring out whether buying actually makes financial sense is worth doing with a full picture of who’s contributing what before a purchase, not just at the point of sale.
Formalizing the split with a written agreement
A co-ownership agreement, separate from the deed and mortgage, is the general tool used to document intentions clearly: what percentage each person owns, how unequal contributions are handled, what happens if one person wants to sell or refinance, and how a future sale’s proceeds get divided. This kind of agreement matters most for buyers who aren’t married, since there’s no default legal framework like the ones that typically apply when a marriage ends and a joint mortgage has to be untangled.
Where this leaves you
Splitting equity fairly starts with documentation, not assumptions. Title type sets the legal default, a written co-ownership agreement can adjust for unequal contributions, and neither of those things happens automatically just because two people are named on the same mortgage. Working out these details before closing tends to be far less stressful than trying to reconstruct who paid for what years later.