Co-Owner Not Paying the Mortgage: Contribution, Buyout, and Partition

If your co-owner has stopped paying the mortgage, you are still fully on the hook for the entire payment, and your credit, the property, and thousands of dollars are at risk if you wait. Every borrower who signed the loan carries what the law calls joint and several liability: the lender can demand the whole payment from you alone, report the missed payment on your credit, and eventually foreclose, regardless of who was “supposed” to pay which half. The practical response is to cover the payment now to protect your credit, document what you’re doing, and then use one of a handful of legal tools (loss mitigation, buyout, refinance, sale, or a partition suit) to end the arrangement and recover what you’ve overpaid.

Do These Things This Week

Speed matters more than fairness right now. The credit reporting and foreclosure clocks don’t care whose turn it was.

Make the full payment yourself. Once a payment is 30 days past due, the servicer reports it to all three major credit bureaus, and that late mark hits every borrower’s report regardless of who caused it. Covering the payment buys you time and protects your score.
Put your co-owner on written notice. Send an email, a certified letter, or both. State the amount they owe and the deadline. That paper trail is the evidence you’ll rely on later in any contribution claim or partition accounting.
Call the mortgage servicer. Ask about forbearance, loan modification, and other loss mitigation options. Once you submit a complete application, the servicer is required to evaluate you for every program available.¹
Pull your records together. Bank statements, payment confirmations, the mortgage agreement, the deed, and any written arrangement between you and your co-owner about who pays what. You’ll need all of it.

Most mortgages charge a late fee once payment runs past the grace period, typically 10 to 15 days after the due date, commonly around 4% to 5% of the overdue amount on conventional loans.² If enough payments pile up, the acceleration clause in your loan lets the lender demand the entire remaining balance at once rather than just the arrears. Catching up before the lender formally accelerates is possible; catching up after is much harder.³

Use the 120-Day Window Before It Closes

Federal rules give you a real buffer. Your servicer cannot file the first legal notice to start foreclosure until you’re more than 120 days delinquent.⁴ If you submit a complete loss mitigation application during that window, the servicer is blocked from starting foreclosure while it evaluates you.¹

This is the step people most often waste. If your co-owner has walked away from the payments, don’t wait to see whether they’ll come back. Get a loss mitigation application in front of the servicer while the 120-day clock is still running.

Recovering What You’ve Overpaid

If you’ve been covering your co-owner’s share, you have three legal avenues to get made whole. Which one fits depends on whether you want to keep the property, sell it, or just get reimbursed.

Contribution Claim

A contribution claim asks the court to order your co-owner to reimburse you for the share of expenses you covered on their behalf. You show that you paid more than your ownership interest required, backed up by bank statements, canceled checks, and the mortgage agreement. The claim can stand alone or ride along with a partition suit.

Breach of Contract

If you and your co-owner signed a written agreement about who pays what, breach of contract is the cleanest theory. You show the agreement, prove they violated it, and ask for damages. Without a written agreement, you’re arguing general equity instead of specific terms, which is harder to win.

Partition Suit

A partition suit asks a court to divide or sell the property when co-owners can’t agree on what to do with it. For residential property, courts almost always order a partition by sale rather than trying to split the house physically. The property is sold, the mortgage is paid off from the proceeds, and what’s left is divided by ownership share.

Partition matters for a second reason: during the process, courts conduct an accounting that adjusts each owner’s share based on who actually paid the mortgage, taxes, insurance, and maintenance. If you’ve been carrying your co-owner for months, this is where you get credit for it. Expect attorney fees between $5,000 and $30,000 or more depending on how contested things get. It’s expensive, but it gives you a definitive ending when nothing else does.

Ending the Co-Ownership Cleanly

If the working relationship is over, ending it deliberately beats letting the situation drift toward foreclosure. Three routes exist, and each has a trap.

Buyout

One co-owner buys the other out and becomes sole owner. Get a professional appraisal (roughly $300 to $600 for a standard residential property) to establish fair market value. The buying co-owner then refinances the mortgage in their own name, and the departing co-owner signs a quitclaim deed.

Here’s the trap: a quitclaim deed transfers ownership, but it does not remove the departing co-owner from the mortgage. The mortgage is a separate contract with the lender. Until the loan is refinanced or the lender formally releases the departing borrower, that person remains liable for the debt even though they no longer own the property.² Never sign a quitclaim deed until the refinance is lined up to close.

Refinance Into One Name

Refinancing lets one co-owner take over the mortgage entirely and releases the other from liability. The remaining co-owner has to qualify for the new loan on their own income, and if missed payments already dinged their credit, approval gets harder. Pair the refinance with a quitclaim deed from the departing owner.

Selling the Property

If neither of you wants to keep it, selling and splitting the proceeds is the cleanest exit. The mortgage is paid off at closing and the remainder is divided by ownership share, adjusted for any contribution imbalance you agree to. If your co-owner refuses to cooperate on listing price or repairs, a partition suit may be the only way to force a sale.

The Due-on-Sale Clause

Most mortgages contain a due-on-sale clause that lets the lender demand full repayment when the property is transferred. Federal law carves out exceptions the lender cannot enforce against, including transfers to a spouse or children, transfers under a divorce decree, transfers into a living trust where the borrower stays a beneficiary, and transfers on a co-owner’s death.⁵ If your buyout or title transfer doesn’t fit one of those categories, get the lender’s consent or handle the transfer through a refinance.

If Foreclosure Is Closing In

Foreclosure punishes both co-owners equally: you lose the property regardless of who was paying. In judicial foreclosure states, the lender files a lawsuit, which gives you time to contest or negotiate. In non-judicial states, the process is streamlined and offers fewer chances to intervene. The 120-day pre-foreclosure period applies in either case.⁴

Two off-ramps hurt less than a completed foreclosure. A loan modification changes the terms of your existing loan to make payments affordable. A short sale lets you sell for less than the balance with lender approval. Both require cooperation between co-owners and the servicer, and neither is guaranteed, but either beats the alternative.

A completed foreclosure stays on every co-owner’s credit report for seven years from the first missed payment that led to it.⁶ And if the foreclosure sale doesn’t cover the loan balance, the lender may pursue a deficiency judgment against the borrowers for the shortfall. Many states restrict or prohibit deficiency judgments after residential foreclosure, but protections vary. Where they’re allowed, the lender generally has to prove the property sold at a fair price.⁷

If Your Co-Owner Files Bankruptcy

A bankruptcy filing by your co-owner changes the board. The moment the petition is filed, an automatic stay halts collection activity against the debtor, including foreclosure on property in the bankruptcy estate.⁸ For the co-owner who isn’t in bankruptcy, that can freeze the situation in place: the lender may need permission from the bankruptcy court before proceeding, even if you’re current and ready to resolve things.

If your co-owner files Chapter 7, the trustee can sell their ownership share to pay creditors, which may leave you with a stranger as your new co-owner. The federal homestead exemption for 2026 lets an individual filer protect up to $31,575 of equity in their primary residence (double for married couples filing jointly), and many states have their own homestead exemptions that may be higher.⁹ If your co-owner’s equity exceeds the available exemption, the trustee has an incentive to liquidate their interest. Talk to a real estate attorney immediately, because your options may depend on acting before the trustee does.

Tax Effects People Miss

Resolving a co-ownership dispute can generate tax bills you didn’t plan for.

Mortgage interest deduction. If you’re paying the whole mortgage, you might expect to deduct all the interest. The IRS only lets each borrower deduct interest they actually paid. If you’re not the borrower who receives Form 1098, you report your share on a separate line of Schedule A and attach a statement explaining the split.¹⁰ The co-owner who isn’t paying loses the deduction; the paying co-owner claims what they actually paid.

Capital gains on a sale or buyout. When co-owned property is sold, each owner may owe capital gains tax on any profit above their share of the original purchase price. If the property was your primary residence and you lived there for at least two of the last five years, you can exclude up to $250,000 in gain, or $500,000 for married couples filing jointly.¹¹ For 2026, long-term capital gains above the exclusion are taxed at 0%, 15%, or 20% depending on your total taxable income. A buyout can trigger capital gains for the departing co-owner if the buyout price exceeds their original cost basis.

Quitclaim as a gift. If a co-owner transfers their interest via quitclaim for no money in return, the IRS treats that as a gift. Gifts exceeding $19,000 in value during 2026 require the donor to file a gift tax return, though no tax is owed until cumulative lifetime gifts exceed $15,000,000.¹²

1
Consumer Financial Protection Bureau. 1024.41 Loss Mitigation Procedures
2
Consumer Financial Protection Bureau. What Are Late Fees on a Mortgage?
3
Legal Information Institute. Acceleration Clause
4
eCFR. 12 CFR 1024.41 – Loss Mitigation Procedures
5
Office of the Law Revision Counsel. 12 USC 1701j-3 – Preemption of Due-on-Sale Prohibitions
6
Consumer Financial Protection Bureau. If I Lose My Home to Foreclosure, Can I Ever Buy a Home Again?
7
Legal Information Institute. Deficiency Judgment
8
Office of the Law Revision Counsel. 11 USC 362 – Automatic Stay
9
Office of the Law Revision Counsel. 11 USC 522 – Exemptions
10
Internal Revenue Service. Publication 936 – Home Mortgage Interest Deduction
11
Office of the Law Revision Counsel. 26 USC 121 – Exclusion of Gain From Sale of Principal Residence
12
Internal Revenue Service. What’s New – Estate and Gift Tax