Lending Money to Family: How to Do It Without Destroying the Relationship

Lending money to a family member is an act of generosity that often turns into a source of lasting resentment. The loan becomes the subtext of every family gathering. The borrower feels judged; the lender feels taken advantage of. Other family members take sides. Relationships built over decades fracture over amounts that wouldn't require a second thought if they involved a stranger and a bank.

This doesn't have to be the outcome. Family loans can work — and they do, regularly — when the parties treat them with the same seriousness they'd apply to any other financial transaction. The key is documentation, and the most important document is a promissory note.

Why Documentation Helps the Relationship, Not Just the Lender

There's a common belief that formalizing a family loan is cold or signals distrust. The reality is the opposite. A written agreement with clear terms removes ambiguity — the number one cause of family loan disputes. When repayment is expected, how much, how often, and what happens if the borrower hits a rough patch: these questions need answers, and getting those answers in writing before the money changes hands is far easier than arguing about them a year later.

The borrower benefits too. A clear promissory note protects them from vague and shifting expectations. If Aunt Margaret says "just pay me back when you can" and then starts making pointed comments at Thanksgiving about the kitchen renovation she can't afford, a written note with agreed terms gives the borrower a defensible position. The obligation is defined. There's no room for unilateral renegotiation after the fact.

IRS Rules: The Applicable Federal Rate (AFR)

This is the part most people don't know: if you make a below-market loan to a family member, the IRS may treat the forgone interest as a taxable gift. The IRS publishes the Applicable Federal Rate (AFR) monthly — the minimum interest rate for loans to be treated as loans rather than gifts. In mid-2025, the short-term AFR for loans up to three years was approximately 4–5% annually.

If you lend money at below the AFR, the IRS imputes interest: it treats the lender as having received the AFR interest and the borrower as having received a gift in that amount. The lender may owe income tax on imputed interest income, and the gift may need to be counted toward the annual gift tax exclusion ($18,000 per person in 2024).

The good news: for loans under $10,000, the IRS generally doesn't require any minimum interest rate. For loans between $10,000 and $100,000, special rules apply (imputed interest only applies if the borrower has net investment income over $1,000). For loans over $100,000, charging at least the AFR is the cleanest approach.

The Gift Tax Exclusion Alternative

If the amount is small and you don't expect — or particularly care — about being repaid, simply making it a gift is cleaner. You can give up to $18,000 per year per recipient (2024 exclusion) without any gift tax filing requirement. If you're married, you and your spouse can together give $36,000 to one person in a year. Amounts above the annual exclusion count against the lifetime gift and estate tax exemption ($13.61 million in 2024 for federal purposes) but don't necessarily create a tax bill.

Making it a gift avoids the enforceability conversation entirely and eliminates the relationship stress of a debt obligation. The downside: you've genuinely given it away, and the family dynamics implications of giving a large gift to one child while others receive nothing may create their own problems.

What to Include in a Family Promissory Note

A family loan promissory note doesn't need to be complicated, but it should include: the exact amount lent, the date the loan was made, the interest rate (at least the AFR for larger loans), the repayment schedule (monthly installments, lump sum at a specific date, or demand basis), what happens if a payment is missed, and whether the note is secured by any collateral.

It should be signed by the borrower — and ideally witnessed or notarized. The lender should keep the original; the borrower should have a copy. The lender should actually deposit or transfer the money formally (bank transfer with a clear memo, not cash) so there's a paper trail.

If They Don't Repay

If a family member defaults on a documented promissory note, the lender has two practical choices: pursue the legal remedy (file in civil or small claims court, get a judgment, attempt to collect) or write it off. A written-off loan may be deductible as a bad debt on the lender's taxes — but only if the loan was documented and genuine. The IRS scrutinizes family loan deductions carefully; the documentation that shows the loan was real and was intended to be repaid is the same documentation that supports the deduction.

The promissory note is the document that makes the difference — both legally and in the family relationship. It transforms a complicated emotional transaction into a straightforward financial one.