What Interest Rate Should You Actually Charge a Family Member?

Your brother needs twelve thousand dollars to consolidate some debt, and you have it sitting in savings. You want to help without being a bank about it, so your first instinct is to charge no interest at all. Here is what actually happens: that generous zero-percent handshake can create a tax problem for you, because of a rule called the Applicable Federal Rate (AFR) that most families have never heard of.

Picking a rate for a family loan is really about finding the space between two invisible walls. There is a floor set by federal tax law and a ceiling set by your state. Charge below the floor and you invite an imputed-interest problem. Charge above the ceiling and you may violate usury law. The comfortable answer lives in between.

The floor: why zero percent can backfire

When you lend money to family at little or no interest, the Internal Revenue Service (IRS) may treat it as a below-market loan under Section 7872 of the tax code. The rule imagines that you charged a minimum rate, the Applicable Federal Rate, and then treats the interest you did not actually collect as if you had. That phantom interest is called imputed interest, and in a family setting it can be treated as both interest income to you and a gift back to the borrower.

The AFR is published every month by the IRS and comes in short-term, mid-term, and long-term versions depending on how long the loan lasts. It is generally a modest rate, often lower than what a bank would charge, so meeting it is not painful. The point is simply to charge at least that much so there is nothing for the IRS to impute.

It helps to match the version of the AFR to the length of your loan. A loan you expect repaid within three years looks to the short-term rate, a loan running up to nine years uses the mid-term rate, and anything longer uses the long-term rate. You lock in the rate that applies at the time you make the loan, so you are not chasing a moving target every month. Once the note is signed at a qualifying rate, the loan is set.

The small-loan exception worth knowing

There is real relief built into the law for smaller loans. For a gift loan directly between two individuals, the imputed-interest rules generally do not apply on any day the total owed between you stays at or below ten thousand dollars, as long as the money is not used to buy income-producing investments. So if you are lending your sister four thousand dollars for car repairs, you can likely charge nothing and never think about the AFR again.

Once a loan climbs past that ten-thousand-dollar threshold, the floor matters, and charging at least the AFR is the clean way to stay out of trouble. Do not treat this as a firm personal-planning number for a large or unusual loan, though. Confirm the current rules and rates on irs.gov, and talk to a tax professional if the amount is significant.

The ceiling: your state usury cap

At the other end sits usury law, which sets the maximum interest a lender may legally charge. These caps are set by each state, so the limit in Texas is not the limit in New York, and some states treat personal loans between individuals differently from commercial ones. Charge above your state cap and the interest can become unenforceable, and in some places the penalties reach further than that.

You are almost certainly not going to charge a usurious rate to your own brother. Still, it is worth knowing where the ceiling is, especially if you were tempted to add a steep late-payment penalty or a high rate to a longer note. Our usury limit checker is a quick way to see the general cap where you live before you write a number into the document.

The ceiling matters most in the situations that do not feel like family loans at all. If a relative asks you to fund a small business, or the loan carries a penalty rate for missed payments, the effective interest can climb higher than you realize. That is exactly when a rate you thought was generous can bump into your state limit. Checking the cap first costs nothing and keeps a well-meant loan from becoming legally shaky.

Finding the fair number in the middle

So the practical range is clear: at least the AFR if the loan is large enough to matter, and comfortably below your state usury cap. Within that space, a fair family rate is usually a modest one, chosen so the loan feels real without feeling predatory. Many people land somewhere near what a very safe savings account or bond might pay, which happens to sit close to the AFR anyway.

The rate is only fair if it is written down. A verbal agreement to pay some interest someday tends to evaporate the moment money gets tight. Put the rate, the schedule, and the total in a proper promissory note so both sides remember the same deal. If you want to see how a given rate translates into monthly payments, our loan payoff calculator makes the tradeoffs visible before anyone commits.

There is a relationship benefit to charging a real rate, too. A loan with a clear interest figure and a schedule feels like a genuine agreement between two adults rather than an open-ended favor. That structure tends to get repaid, precisely because it feels like a commitment. A zero-interest handshake, by contrast, is the kind of arrangement that quietly slides to the bottom of the borrower's priority list.

A simple way to decide

Start with the size of the loan. If it is small and stays under the ten-thousand-dollar gift-loan threshold, you can charge nothing with a clear conscience. If it is larger, set the rate at or a little above the current AFR so imputed interest never becomes your problem, then sanity-check that number against your state cap. Write it into the note, keep the payments realistic, and you have been both a good sibling and a careful lender. Those two things do not have to be in tension.

Sources

• IRS, Applicable Federal Rates
• 26 U.S. Code Section 7872, Treatment of loans with below-market interest rates
• IRS, Frequently Asked Questions on Gift Taxes