S-Corp Shareholder Loans: The $10,000 Below-Market Trap
If your S-corp carries shareholder loans with no interest charged, or interest below the applicable federal rate, the IRS doesn’t just let that slide. Under Section 7872 of the Internal Revenue Code, below-market shareholder loans get interest imputed anyway. There’s a $10,000 exception, but it’s narrower than most owners assume, and missing it means both unreported income and an unplanned distribution showing up on your return.
When Shareholder Loans Count as Below-Market
Section 7872 reaches any loan “directly or indirectly between a corporation and any shareholder of such corporation,” with no minimum ownership percentage. That covers the common pattern: the corporation advances cash to a shareholder for a personal expense, or a shareholder covers a cash-flow gap and the company never pays it back with interest. The test differs depending on whether the loan is a demand loan or a term loan. A demand loan — payable whenever the lender asks — is below-market if the interest rate charged is below the applicable federal rate (AFR) in effect for the period. A term loan, with a fixed repayment schedule, is below-market if the amount loaned exceeds the present value of the required payments, discounted at the AFR in effect when the loan was made.
This is a separate issue from shareholder basis and the AAA. Basis tracks what you’ve already put into or taken out of the company; Section 7872 is about what you should have been charging on money that moved between you and the corporation but hasn’t been repaid with market interest.
The $10,000 Exception — And What Voids It
Corporation-shareholder loans get a narrow de minimis exception under Section 7872(c)(3): on any day the aggregate outstanding balance between the shareholder and the corporation is $10,000 or less, the imputed-interest rules don’t apply that day. The test runs day by day, not year by year. A balance that sits at $8,000 all year stays exempt. A balance that climbs to $11,000 for even a few weeks brings those weeks back into the rule, and every other outstanding loan between the same shareholder and corporation counts toward that $10,000 aggregate. One caution for term loans: under Section 7872(f)(10), once the rules apply to a term loan on any day, they keep applying for the life of the loan, even if the balance later falls back under $10,000.
The exception disappears entirely, at any balance, if one of the principal purposes of the arrangement is avoiding federal tax. The statute requires only that tax avoidance be one of the principal purposes, not the sole one. A shareholder who routinely draws cash as an “advance” instead of taking it as salary or a documented distribution — particularly where reasonable compensation is already thin — is exactly the pattern this carve-out is aimed at.
How the IRS Calculates the Imputed Interest
Once a loan is below-market and the exception doesn’t apply, the shortfall is called “forgone interest” — the difference between what would have accrued at the AFR and what was actually charged. The rate used depends on the loan type. A term loan uses the AFR in effect under Section 1274(d) for the month the loan was made, compounded semiannually, for the life of the loan. A demand loan uses the federal short-term rate for the period the interest is being measured, which moves every month.
The AFRs for October 2026, published monthly by the IRS, illustrate the range: the short-term rate is 4.25% annually, the mid-term rate is 4.61%, and the long-term rate is 5.22%. A $50,000 interest-free demand loan from an S-corp to its shareholder, outstanding for a full year at the short-term rate, imputes roughly $2,125 in forgone interest for that period alone — all of it income somewhere on a return, even though no cash changed hands for interest.
What the Imputed Amount Actually Is on Your Return
Section 7872 treats the forgone interest as two simultaneous, offsetting transfers. First, the corporation is treated as paying that amount to the shareholder. Second, the shareholder is treated as paying it right back to the corporation as interest. The first leg is where the S-corp result diverges from the C-corp answer most practitioners learned the rule from. For a C-corp, that payment is a dividend taxed under Section 301. For an S-corp the payment is instead a distribution under Section 1368. If the company has never been a C-corp and has no accumulated earnings and profits, that means nontaxable to the extent of the shareholder’s stock basis, and capital gain only once basis runs out; an S-corp still carrying earnings and profits from C-corp years can see part of the distribution taxed as a dividend once it exceeds the accumulated adjustments account.
The second leg is real interest income to the corporation — and because an S-corp’s income passes through, that interest income shows up on every shareholder’s K-1 pro rata, not just the shareholder who took the loan. A loan one owner never repays with interest quietly raises every other owner’s taxable income.
The Paper Trail That Protects You
None of this is a reason to avoid shareholder loans — it’s a reason to document them like loans. A written note with a stated interest rate at or above the AFR in effect when the funds moved, a repayment schedule, and actual payments that track it will keep Section 7872 from applying at all. Where a loan is really compensation or really a distribution in disguise, the IRS and the courts will often recast it as what it functions as, which is its own problem and connects directly to how reasonable compensation gets scrutinized on audit. If you’re carrying a shareholder balance above $10,000 right now with no interest charged, that’s worth fixing before year-end, not after the K-1s go out. Talk to us about structuring it correctly.