Loaning Money to Your S-Corp: The Right Way to Do It

At some point in the life of almost every small business, the owner moves money from their personal account into the company. Sometimes it’s to cover payroll during a slow stretch. Sometimes it’s to fund a piece of equipment before a loan comes through. It feels routine—your money, your company, your call.

But for S-corporation owners, how that transfer is classified and documented determines how it’s treated for tax purposes—and the difference between doing it right and doing it casually can show up years later, when you least expect it.

When structured correctly as a genuine loan, the transfer creates something called debt basis, one of the most useful tax tools available to an S-corp owner. When it’s not documented—or the IRS decides it doesn’t look like a real loan—it gets recharacterized as a capital contribution or a distribution, and the tax treatment changes entirely.

When you put money into your S-corp, it is one of two things in the eyes of the tax code.

A capital contribution increases your stock basis—the equity you hold in the corporation. It does not create a liability for the company. You don’t get it back as a formal repayment; it comes back eventually through distributions or on the sale of the business.

A shareholder loan creates a formal debt obligation. The company owes you money, with interest, on documented terms. This increases your debt basis—a separate category from stock basis, with its own rules and advantages.

Most owners don’t make this choice consciously—they move money and let the bookkeeper sort it out. That’s where the problems begin. With no promissory note, no interest rate, and no repayment schedule, the IRS has no reason to call it a loan. They’ll call it a contribution, and you lose the debt basis that came with it.

Why the distinction matters beyond basis

The classification also affects what happens if the company can’t repay. If a genuine loan goes bad, you may be able to claim a bad-debt deduction under IRC §166. If it’s recharacterized as a contribution, there’s no bad debt—just a loss on your investment, under different rules with different limitations.

S-corporations pass income, losses, deductions, and credits through to shareholders’ personal returns—the feature that makes the structure attractive, because you avoid the double taxation of a C-corp.

But the IRS caps how much of those losses you can actually deduct: only up to your basis in the corporation. Under IRC §1366(d), losses that exceed your basis aren’t deducted—they’re suspended and carried forward until you have enough basis to absorb them.

Your total basis in an S-corp is the sum of two components:

This is why shareholder loans matter strategically. If your stock basis has been reduced to zero by prior losses or distributions, an outstanding loan to the company gives you additional basis to absorb current-year losses. Without the loan—or without the documentation to prove it’s genuine—that basis doesn’t exist, and your losses are stuck.

One critical requirement: the loan must be direct

The IRS has consistently held—and the Tax Court has affirmed—that debt basis arises only from a loan made directly from the shareholder to the corporation. Guaranteeing third-party debt does not create debt basis, even if you’re personally on the hook. This was settled in Selfe v. United States and reinforced by the final regulations under Treas. Reg. §1.1366-2(a)(2). The money has to actually come from you, into the company, with documentation.

Because shareholders have an obvious interest in characterizing transfers as loans, the IRS scrutinizes these transactions carefully. Courts apply a multi-factor test to decide whether a purported loan has economic substance as genuine debt.

No single factor is determinative—courts look at the totality of the circumstances. But in practice the first four carry the most weight. A signed note with an interest rate, a repayment schedule, and actual payments is very difficult for the IRS to recharacterize.

You cannot make an interest-free loan to your own S-corp and have it treated as genuine debt. The IRS requires related-party loans to charge interest at or above the Applicable Federal Rate (AFR)—a minimum rate published monthly under IRC §1274(d).

If you charge no interest, or a rate below the AFR, the IRS applies imputed interest rules under IRC §7872. It treats the transaction as if interest were charged at the AFR—creating phantom income for you, the lender, even if no money actually changed hands.

For most shareholder loans—typically short-term—you’ll use the short-term AFR in effect during the month the note is executed. The rate is fixed at origination for fixed-rate notes. Confirm the current rate before signing.

The IRS does not give credit for good intentions. Here is what a properly documented shareholder loan requires.

The note is step one—and the one most owners skip. Our template already includes the AFR interest language, repayment options, the debt-basis and corporate-authorization clauses, and an Exhibit A for your transfer evidence.

When the corporation repays a shareholder loan, the tax treatment depends on whether the loan created debt basis and how that basis has been used.

If debt basis was never reduced

If no losses were allocated against your debt basis during the life of the loan, repayment of principal is not taxable. You’re simply getting your money back; the liability is extinguished and your debt basis drops to zero.

If debt basis was reduced by losses

Under IRC §1367(b)(2), when losses exceed stock basis they reduce stock basis to zero and then reduce debt basis. If the loan is later repaid while debt basis is below the original amount, the difference between the repayment and the remaining debt basis is taxable—generally as ordinary income or capital gain depending on the circumstances. This is why a current, accurate basis schedule matters.

Interest payments

Interest received from the corporation is ordinary income to you as the lender, reported on Schedule B in the year received. The corporation generally deducts the interest expense under IRC §163, subject to applicable limitations.

Treating personal and business finances as interchangeable

The most common—and most damaging—pattern is moving money back and forth without documentation or consistent characterization. One transfer gets called a loan, another an advance, a third nobody remembers. By the time there’s an audit or a sale, no one can reconstruct what was what, and the IRS makes the determination for you.

Backdating loan documentation

Creating a note after the fact—especially with a date that predates execution—is a serious problem with legal and ethical implications. The correct response to a prior undocumented transfer is to characterize it accurately going forward, not to retroactively paper it.

Using loan guarantees as a substitute for direct loans

Guaranteeing a bank loan to your corporation does not create debt basis, even though you’re personally at risk. As noted above, this has been settled law since Selfe. The transfer has to be direct—from your account to the company’s.

Neglecting basis tracking

S-corp basis tracking is not automatic. QuickBooks doesn’t do it; your tax software doesn’t do it. It’s a separate calculation updated annually for income, losses, distributions, and loan activity. Without it, you can’t know whether a distribution is taxable, a loss is deductible, or what a repayment will cost you.

Before or at the time of any shareholder loan to your S-corp, confirm each of the following.