You can deduct interest paid on a family loan for your mortgage, but only if the loan is secured by a recorded mortgage or deed of trust against your home. An informal note or a handshake agreement does not qualify, no matter how much interest you actually paid. The IRS treats a family loan exactly like a bank loan for this purpose: no valid lien, no home mortgage interest deduction.
That single requirement trips up more families than any other part of a private home loan. Search forums like TurboTax's community and you will find dozens of borrowers who paid thousands in interest to a parent or sibling, only to learn at tax time that an unrecorded note leaves them with nothing to claim. Here is the full test, the paperwork it actually takes, and the math on whether it is even worth doing.
The Four-Part Test for the Family Loan Mortgage Interest Deduction
IRS Publication 936 does not carve out a special category for loans between relatives. Your family loan has to clear the same bar as any home loan:
- It has to be secured debt. You sign an instrument, a mortgage, deed of trust, or land contract, that makes your home collateral and lets the lender act against the property if you default.
- That instrument has to be recorded (or otherwise perfected) under your state's law. A note that sits in a drawer, unsigned by a notary and unfiled at the county recorder's office, does not create secured debt.
- The loan has to fund a qualified home. Buying, building, or substantially improving your main home or a second home counts. Using the money to pay off credit cards or fund a business does not, even if your home ends up as collateral.
- You have to itemize. The deduction lives on Schedule A. If you take the standard deduction, none of this matters.
| Requirement | What satisfies it | What fails it |
|---|---|---|
| Secured debt | A signed mortgage or deed of trust naming your family lender as the secured party | A promissory note with no lien attached |
| Recorded lien | Filed with the county recorder or land records office | An unrecorded, unnotarized note kept between the two of you |
| Qualified use | Buying, building, or substantially improving your main or second home | Debt consolidation, tuition, or a business loan secured by the house as an afterthought |
| Itemizing | You file Schedule A and your itemized total beats the standard deduction | You take the standard deduction |
Miss any one of the four and the interest you pay your parents, your sibling, or your in-laws is just personal interest. Personal interest has not been deductible since the 1986 Tax Reform Act killed it off, family or not.
Step One Is a Lien, Not a Loan Agreement
A loan agreement or promissory note establishes that money changed hands and spells out the repayment terms. It does not, by itself, secure the debt. For more on what that document should cover, see what a promissory note is and whether family loans need one.
To get from "loan" to "secured home loan," someone has to draft and record a mortgage or deed of trust naming your parent, sibling, or other family lender as the secured party, exactly the way a bank would file one after closing. In most states this means:
- A licensed attorney or title company prepares the security instrument.
- The document is signed, notarized, and filed with the county recorder or land records office.
- The lender receives a recorded lien position, which also means they could theoretically foreclose if you stop paying. Families rarely enforce this, but the legal right has to be real for the IRS to treat the debt as secured.
This step costs money, usually a few hundred dollars in attorney and recording fees. Skipping it is the single most common reason a family mortgage interest deduction gets disallowed on audit.
How Do You Report It Without a Form 1098?
Your parents are not a bank, so they will not send you a Form 1098 each January. That does not exempt you from the paperwork; it just changes where it goes.
Per Publication 936, you report the interest on Schedule A, line 8b, and you write your lender's name, address, and taxpayer identification number on the dotted lines next to that line. Your lender needs your Social Security number too, since they must report the interest as taxable income on Schedule B. A Form W-9 is the cleanest way to exchange that information before tax season, not during it.
Leave the TIN blank and the IRS can assess a $50 penalty for each missing piece of required information, on top of possibly denying the deduction outright while it sorts out the mismatch.
Does the Family Loan Interest Deduction Actually Save You Money?
Run the numbers before you spend money recording a lien. Say your parents lend you $500,000 to buy a house, secured by a properly recorded deed of trust, at 5.5% interest. First-year interest runs close to $27,000. Add $8,000 in property taxes and you are at roughly $35,000 in itemizable expenses.
For 2026, the standard deduction is $16,100 for single filers and $32,200 for married couples filing jointly, per the IRS's official inflation adjustments for tax year 2026. A single filer in this example clears the standard deduction by about $18,900 and gets real value from itemizing. A married couple filing jointly clears it by only about $2,800, which is still a benefit, just a much smaller one once you weigh it against the cost of recording the lien in the first place.
Run your own numbers with the family loan calculator before you decide the paperwork is worth it, and use the amortization schedule calculator to see how much of each payment is interest versus principal in year one versus year ten, since that ratio, and the size of your deduction, shrinks every year as the loan amortizes.
The AFR Trap Runs on a Separate Track
Being secured does not get you out of the IRS's minimum interest rules. If you charge your child or sibling less than the Applicable Federal Rate for a loan of that size and term, the IRS treats the difference as imputed interest, taxable to the lender and potentially a gift from the lender to the borrower, regardless of whether the loan is secured.
These are two separate tests. A loan can be perfectly secured and still trigger imputed interest if the rate is too low, or it can charge a fair market rate and still fail the deduction test because nobody recorded the lien. Check the current month's minimum rate with the AFR and minimum interest calculator before you set the note rate, since AFRs are published monthly and change every cycle.
Four Ways Families Accidentally Disqualify the Deduction
- Treating the note as a formality. A signed promissory note with no recorded mortgage or deed of trust behind it is unsecured debt, deduction denied.
- Using an open-ended demand note. Loans payable "on demand" with no fixed term can complicate both the secured-debt test and the AFR calculation, since the applicable rate depends on the loan's term.
- Mixing loan proceeds. If part of the money buys the home and part pays off unrelated debt, only the portion used for the home qualifies as acquisition debt.
- Letting the lien lapse. If the family loan gets refinanced, modified, or partially forgiven later, the security instrument needs to be updated to match. An outdated lien can undercut the deduction on audit.
What About Refinances and Rental Property?
The same secured-debt rule applies if your parents refinance an existing mortgage rather than fund a purchase, as long as the new debt does not exceed the balance being refinanced plus the cost of home improvements. For loans on a rental or investment property, the interest is not home mortgage interest at all. It is reported as a rental expense on Schedule E instead, and the secured-debt requirement does not apply the same way, so talk to a tax professional if the property in question is not your primary or second home.
None of this is a substitute for a CPA or tax attorney who can look at your specific state's recording rules and your full return. It is a map of the requirements so you walk into that conversation knowing what questions to ask.
Put the Paperwork in Place Before You Wire the Money
The deduction only works if the security instrument exists before the IRS ever looks at your return, not after. If you are still structuring the loan, create a free family loan agreement that documents the terms clearly, then take it to a local attorney or title company to convert it into a recorded mortgage or deed of trust. For the bigger picture on how a family loan is taxed on both sides, see the complete guide to family loans and taxes.
If your family is financing an entire home sale rather than a purchase loan, the rules shift again. See seller financing a home to a family member for the installment-sale side of that transaction, and the different types of family mortgage structures for how lump-sum, amortizing, and interest-only notes compare once the loan is in place.
Once the loan is running, track payments and interest automatically so you and your family lender both have a clean record if the IRS, or a future refinance lender, ever asks for one.
