Valuing your share of a home when you bought with an unmarried partner

When two people buy a home together and one contributes significantly more toward the down payment, the eventual question of who is owed what depends entirely on how ownership was structured, and on having a clear method to value the property when it comes time to split it.

Joint tenancy versus tenants in common

Joint tenancy assumes equal shares regardless of contribution. Tenants in common allows unequal percentages to be registered on title, for example seventy-thirty, which matches the actual down payment split. Choosing the wrong structure at purchase makes any later valuation dispute far harder to resolve.

Agree on a valuation method before you need one

A cohabitation agreement should specify how the property will be valued if one partner wants to sell or buy out the other, whether that means an independent appraisal, an average of multiple agent opinions, or another agreed process. Deciding this while the relationship is stable removes a major source of conflict later.

• Record each partner's actual contribution and its source
• Define how ongoing costs like mortgage, taxes, and repairs are split
• Set a specific valuation method for a future buyout or sale
• Decide how much time a buyout has to be completed once triggered

Both names on the mortgage complicates a clean split

Even with unequal ownership percentages, a lender holds both borrowers responsible for the full mortgage. If a buyout happens, the remaining partner has to qualify to remove the other from the loan, and that requires a fresh application, not just a private agreement between the two of you.

Gifted funds add another layer

If a parent contributed toward one partner's share, lenders require a signed gift letter confirming it is not a loan. That documentation should also feed into how ownership percentages and any future valuation split are calculated, since an undocumented gift can become a dispute later.

Get the number right from the start

A property valuation done at purchase, paired with a written agreement on how contributions and future value will be split, protects both partners regardless of what happens down the road. It is far cheaper to arrange upfront than to argue over years later.