United States · 7 min read · Laddered Editorial · 18 Jun 2026

Buying a House Together When One Person Pays More: How to Structure Unequal Ownership

One of you brings $60,000 to closing, the other brings $20,000. Here's how American co-buyers turn uneven money into ownership shares that hold up — on the deed, at the IRS, and at sale.

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This article is general information only and is not legal, financial, tax, or property advice. Consider advice from a qualified professional for your circumstances.

The $60,000 / $20,000 problem

Two people decide to buy a place together. One's been saving since college and brings $60,000; the other's just out of grad school and brings $20,000. Everyone agrees it'll get "evened out eventually," both names go on the deed, and the subject quietly never comes up again — until the house sells, and $200,000 of appreciation needs dividing, and the person who put in three times as much discovers the deed says 50/50.

The math here is easy. What needs actual care is deciding what the math should be, and then making the paperwork match.

What the deed says wins

Start with an unromantic fact: when co-owners disagree later, courts look at the deed, not at Venmo history. And the deed forces a choice. Joint tenancy with right of survivorship splits ownership equally, full stop — it has no way to express 75/25. Tenancy in common is the structure that lets each owner hold a defined percentage, which is why it's the standard vesting for co-buyers who aren't married. If your contributions are unequal and your deed says joint tenants, the legal record contradicts your intentions from day one. (Our US guide to co-ownership agreements covers the title options in more depth.)

An undocumented side deal — "we know it's really 70/30" — is worth very little against a recorded deed, and proving one after a falling-out is slow and expensive.

Model 1: shares follow the money

Add up what each person contributes, at closing and ongoing, and set the tenancy-in-common percentages to match. Say the house costs $500,000, you're putting $80,000 down, and you'll split the $420,000 mortgage payments equally:

Person A: $60,000 down plus half the loan — $270,000 of the $500,000, or 54%
Person B: $20,000 down plus half the loan — $230,000, or 46%

The deed records 54/46, and every dollar of sale proceeds later simply follows the percentages. Nothing to remember, nothing to renegotiate.

Model 2: equal shares, with the gap papered as a loan

Some couples and friends genuinely want a 50/50 partnership even though the savings arrived unevenly. That works too — keep the deed equal and treat the $40,000 difference as a documented loan from one owner to the other, with a promissory note, a repayment schedule, and (if you want it enforceable in the worst case) terms a stranger could read and apply. The deposit gap gets repaid off the top at sale, or in installments along the way, and the ownership stays clean at 50/50.

What doesn't work is the third, most popular model: equal deed, equal payments, and a shared memory that someone put in more. That's not a structure. It's an argument with a delayed start date.

Model 3: let the split move with contributions

If one owner will fund the renovation, or cover more of the mortgage in some years than others, a fixed percentage set at closing will drift away from reality. The fix is an adjustment mechanism written into your co-ownership agreement: contributions get logged, and the equity split gets recalculated by an agreed formula at agreed moments (annually, or at sale). This is the most accurate model and the most bookkeeping-hungry one — it only works if the record of who paid what is complete and trusted by everyone. A missing year of records turns your formula into a fight.

The mortgage doesn't care about any of this

Whatever the deed says, a joint mortgage makes each borrower liable for the entire debt. If your co-owner stops paying, the lender comes to you for all of it, and the missed payments land on both credit reports. The full loan also follows each of you into future applications: when you go to buy your next place, most lenders count the whole joint debt against you, not your share. Structure the ownership however you like — the loan remains a three-legged race.

Write down more than the percentages

The paperwork that makes any of these models stick is short:

The deed, vested as tenants in common in your agreed percentages (or equal, if you chose Model 2 with a note).
A co-ownership agreement recording how you got to the split, how monthly costs divide, what happens when someone funds an improvement, and the exit mechanics. (Here's what belongs in it.)
A contribution ledger from day one. The down payment is unforgettable. The $4,200 furnace in year three and who floated the property taxes during a layoff are not — and at sale, that ledger is the difference between a calculation and a negotiation.

There's a tax reason to keep the records too: the IRS lets each co-owner deduct only the mortgage interest they actually paid, so a clean payment history matters every April, not just at sale. (More on co-owner taxes here.)

Keep the number honest

Laddered exists for exactly this: you set the ownership percentages and contribution rules once, and every expense afterward splits by those rules automatically, in one ledger every owner can see. The deal you struck at closing stays visible for the life of the house instead of dissolving into memory.

It doesn't replace professional advice. Have a real estate attorney paper the deed vesting and the co-ownership agreement before closing — especially if the shares are unequal, and doubly so if you're buying with a partner you're not married to. The math is the easy part. Making it enforceable is what the modest legal fee is for.