Applicable Federal Rate (AFR)

The Applicable Federal Rate (AFR) is the minimum interest rate that the Internal Revenue Service (IRS) in the United States requires for private loans. Think of it as the government’s official “friend and family” interest rate. The IRS publishes these rates every month to prevent people from disguising tax-free gifts as zero-interest or low-interest loans. If you lend money to someone—say, your aspiring entrepreneur cousin—at a rate below the AFR, the IRS might step in and say, “Nice try!” They will then calculate the interest you should have earned using the AFR and tax you on that “phantom” income. This is a concept known as imputed interest. The primary goal of the AFR is to ensure that when money changes hands as a loan, there's a fair and taxable amount of interest income associated with it, distinguishing it from a genuine gift which might be subject to gift tax rules.

You might think this is just boring tax code, but for a savvy investor, the AFR is a surprisingly useful tool. It’s not about picking stocks, but about managing your wealth wisely once you’ve built it.

This is the most common scenario. Imagine you've done well with your investments and want to help your child with a down payment on their first home. Instead of just giving them the money (which could have gift tax implications), you can formally lend it to them. By charging them interest at or above the current AFR, you create a legitimate loan in the eyes of the IRS. The beauty is that AFRs are often significantly lower than commercial bank rates. This allows you to help your family in a meaningful way without them having to pay high bank interest, and you avoid creating a messy tax situation for yourself. It's a clean, official, and tax-efficient way to provide support.

If you're investing beyond the stock market, perhaps in real estate or buying a small business, you might encounter seller financing. This is where the seller of the asset acts like a bank, lending the buyer the money to complete the purchase. In these private transactions, the loan agreement must feature an interest rate that is at least the AFR to be considered legitimate by the tax authorities. Whether you are the buyer or the seller, knowing the current AFR is crucial for structuring the deal correctly.

On a broader level, the AFRs offer a quick glimpse into the state of U.S. government debt. The rates are directly based on the yield of various U.S. Treasury securities. While you shouldn't base your entire market strategy on them, watching the trend in AFRs can give you a general feel for the direction of interest rates, a key factor that influences the entire investment landscape.

The IRS doesn't just have one rate; it publishes a table of them each month, categorized by the loan's duration.

• Short-term AFR: For loans with a term of up to 3 years.
• Mid-term AFR: For loans with a term longer than 3 years but not more than 9 years.
• Long-term AFR: For loans with a term longer than 9 years.

Additionally, the IRS provides different rates based on how frequently the interest is calculated, or compounded.

• Annual compounding
• Semiannual compounding
• Quarterly compounding
• Monthly compounding

You simply choose the rate that matches the term and compounding period specified in your loan agreement. You can always find the latest, official AFR tables by searching for “AFR Rulings” on the IRS website.

For the value investor, mastering the game means understanding all the rules, not just those related to financial statements. The AFR is one of those rules.

• Efficient Capital Allocation: A core principle of value investing is smart capital allocation. The AFR provides a tax-efficient mechanism to allocate some of your capital outside the public markets—for instance, to support family or participate in private deals. It turns a potential tax headache into a structured financial tool.
• Avoiding Unforced Errors: Great investors like Warren Buffett emphasize the importance of avoiding stupid mistakes. Not knowing about the AFR when making a private loan is an “unforced error” that can lead to unexpected tax bills and complications. It's a simple piece of knowledge that protects your capital from needless loss.
• Understanding Opportunity Cost: When you lend money at the low AFR, you are making a conscious decision. The opportunity cost is the higher return you might have earned by investing that money elsewhere. The AFR provides a clear baseline, forcing you to think about whether the loan is a form of family support, a strategic private investment, or something in between. This clarity of purpose is the hallmark of a disciplined investor.