S Corp Debt Basis: Creation, Restoration, and Repayment

In an S corporation, debt basis is the tax basis you create by personally lending money to the company, and it lets you deduct pass-through losses after your stock basis has been used up. It is a second tank of loss-absorbing capacity, but only if the loan is genuinely yours, documented properly, and tracked year by year. Get any of those wrong and you can lose deductions permanently or pay unexpected tax on what feels like a simple loan repayment.

What Debt Basis Is and Where It Comes From

Your total basis in an S corporation has two separate components. Stock basis starts with what you paid for or contributed for your shares and moves each year with income, losses, distributions, and nondeductible expenses. Debt basis comes from one place only: money you personally lend to the corporation.

The reason to care about the split is the loss limitation rule. You cannot deduct more in S corporation losses and deductions in a year than the sum of your stock basis and your debt basis.¹ Anything above that combined figure is suspended and carried forward.

There is a strict order. Losses reduce stock basis first, all the way to zero. Only then do they begin eating into debt basis.² That ordering shapes almost everything else that follows, because a reduced debt basis behaves differently from a reduced stock basis when the corporation later pays you back or makes a distribution.

How to Create Valid Debt Basis

The core requirement is a direct economic outlay. You have to lend money to the corporation yourself, creating a real debtor-creditor relationship in which the corporation owes you the funds. If a bank lends to the corporation and you sign as a guarantor, the guarantee alone produces no debt basis.³ Basis only appears if and when you actually pay on the guarantee, and only to the extent of that payment. This is the single biggest difference from a partnership, where entity-level debt can increase a partner’s basis.

The loan also has to be bona fide. Practically, that means a written promissory note with a stated principal, a repayment schedule, and an interest rate at or above the applicable federal rate. Missing pieces invite the IRS to recharacterize the advance as a capital contribution, which builds stock basis instead of debt basis, or as a taxable distribution.

Back-to-Back Loans

When the corporation needs cash the shareholder does not have on hand, a common structure is a back-to-back loan: you borrow from a bank or a related entity, then re-lend those funds to the S corporation under a separate agreement. Courts have accepted this when the shareholder carries real economic risk on both sides. In Ruckriegel v. Commissioner, the Tax Court allowed debt basis where shareholders borrowed from a related partnership and re-lent to the S corporation, because they were obligated to repay the partnership no matter what the corporation did.

The arrangement draws scrutiny. If the funds simply circle through the entities without the shareholder taking on genuine repayment risk, the basis will be denied. The question courts ask is whether the transaction actually made the shareholder poorer in a real, out-of-pocket sense.

Open Account Debt and the $25,000 Threshold

Not every shareholder advance comes with a promissory note. Smaller amounts to cover payroll or a vendor invoice often go in and out informally. The regulations call these undocumented advances “open account debt” and give them a threshold.

If your net outstanding undocumented advances at the corporation’s year-end are $25,000 or less, all the advances are treated as a single debt for basis-adjustment purposes.⁴ Advances and repayments net together, which is much easier to track.

Cross above $25,000 net at year-end and the balance permanently loses open-account status. From that point on, it is treated the same as debt evidenced by a written instrument, and each advance and repayment must be tracked as its own item.⁴ The classification also changes how repayment gain is taxed, discussed further below.

How Losses Reduce Debt Basis

Once stock basis is zero, additional losses reduce your adjusted basis in the debt, not the face amount of the loan. Say you hold $10,000 of stock basis and $50,000 of debt basis and the corporation passes through a $20,000 loss. The first $10,000 wipes out stock basis. The next $10,000 drops your debt basis from $50,000 to $40,000. The note itself is unchanged; the corporation still owes you $50,000. Your tax basis in that receivable is just lower.⁵

Losses beyond your combined stock and debt basis are suspended and carry forward indefinitely.¹ Nondeductible expenses beyond stock basis also flow down and reduce debt basis, but a nondeductible expense that exceeds both stock basis and debt basis is simply gone; it does not carry forward.⁶

If you hold more than one loan to the corporation, the reduction is allocated proportionally across each loan based on their relative adjusted bases. You cannot pick which loan absorbs the hit.

Debt Basis Is Restored Before Stock Basis

The rule that catches shareholders off guard sits on the way back up. Once debt basis has been reduced by losses, it has to be restored before any positive adjustments reach your stock basis.

In any year the corporation shows a “net increase,” meaning positive income items exceed losses, deductions, nondeductible expenses, and distributions, that net increase first rebuilds your reduced debt basis toward its original face amount.⁷ Only after debt basis is whole does the remainder increase stock basis.⁵

An example: prior years reduced your debt basis by $15,000, and the corporation now generates $20,000 of net income. The first $15,000 restores debt basis. The last $5,000 increases stock basis. You still owe tax on the full $20,000 of pass-through income, but both basis figures are moving in the right direction.

Two limits apply. Restoration only reaches debt you already held at the beginning of that tax year, so a mid-year loan does not qualify for restoration until the following year. And you cannot restore basis beyond the original face of the loan reduced by any principal already repaid.⁷

With multiple loans, a net increase first restores basis in any loan being repaid that year, up to what is needed to prevent gain on the repayment. Anything left over is spread proportionally across the remaining loans by their unreduced basis amounts.⁷

Tax on Repayment: Why Documentation Matters

When the corporation repays a loan whose debt basis still equals face value, the repayment is a nontaxable return of capital. The trouble comes when prior losses have pulled debt basis below face. The gap between what you receive and your reduced basis is taxable gain, and the character of that gain depends entirely on how the loan is documented.

Written Notes Produce Capital Gain

A loan evidenced by a written instrument is treated on repayment as a sale or exchange of a capital asset under Revenue Ruling 64-162. Gain is long-term capital if you held the note for more than 12 months and short-term otherwise. For a partial repayment, the payment is allocated proportionally between a tax-free return of basis and a taxable portion. On a $100,000 loan with a $60,000 reduced basis, 40 percent of every dollar repaid is gain.

Open Account Debt Produces Ordinary Income

Without a written instrument, any gain on repayment of open account debt is ordinary income under Revenue Ruling 68-537. Ordinary rates typically run higher than long-term capital gains rates, so the paperwork decision has real dollars behind it. A short promissory note at the outset is often the cheapest tax planning available.

Distributions Do Not Touch Debt Basis

One boundary worth being explicit about: distributions from the corporation do not reduce debt basis, and debt basis is ignored in deciding whether a distribution is taxable.⁸ Only stock basis shelters a distribution. If your stock basis is zero but you hold $50,000 of debt basis, a distribution is not covered by the debt basis. It generates taxable gain.

Shareholders who think of themselves as having plenty of total basis sometimes take distributions on that assumption and find out at filing time that they owe capital gains tax on part or all of the payout.

Interest on the Loan: The AFR Requirement

A shareholder loan to an S corporation is expected to carry interest at or above the applicable federal rate. If the stated rate is below the AFR, Section 7872 treats the forgone interest as if it were actually paid, producing phantom interest income for you and a matching interest expense for the corporation.⁹

A de minimis exception applies when total loans outstanding between you and the corporation never exceed $10,000 on any day; Section 7872 does not apply in that case unless one of the principal purposes of the interest arrangement is tax avoidance.⁹ Above $10,000, stating the AFR from day one is the clean fix.

The awkward result for many S corporation loans is that the corporation is losing money precisely because the shareholder had to lend it funds. The imputed interest deduction on the corporation’s side may sit unused while the shareholder still has to report imputed interest income.

Basis Is Not the Only Hurdle

Having enough combined stock and debt basis clears one gate, not all of them. Two other limitations still stand between a corporate loss and your return.⁸

Under Section 465, you can deduct losses only to the extent you are at risk in the activity, which generally means amounts you contributed and amounts you borrowed on which you are personally liable or have pledged non-activity property.¹⁰ For an active shareholder funding the business with personal cash and direct loans, the at-risk amount usually looks a lot like basis, but not always, particularly with related-party financing.

Section 469 then blocks losses from any activity in which you do not materially participate.¹¹ A passive investor’s S corporation losses are suspended regardless of basis and can only offset passive income, or wait to be released when the entire interest is disposed of in a taxable transaction.

What Happens to Suspended Losses

Losses suspended by the basis limit carry forward indefinitely and are treated as incurred by the corporation in the next tax year as to that shareholder.¹ Add basis later, whether through a capital contribution, a new shareholder loan, or corporate income, and the carryforwards free up.

Two situations put the losses on a clock instead of leaving them open-ended. If the S election terminates, suspended losses can be used only during the post-termination transition period, generally one year after the last day of the final S corporation year, and only against stock basis; debt basis is not available for this purpose. Anything still suspended when that window closes is gone. And if you transfer your stock in any way other than to a spouse or ex-spouse in a Section 1041 transfer, the suspended losses do not follow the shares and are permanently lost to you.¹

Anyone contemplating a sale or a revocation of the S election should look at whether a capital contribution or shareholder loan before the triggering event would unlock losses that would otherwise disappear.

Form 7203 and Keeping the Numbers

The IRS requires S corporation shareholders to file Form 7203, S Corporation Shareholder Stock and Debt Basis Limitations, with their individual return in any year they deduct a loss (including a suspended loss from a prior year), receive a non-dividend distribution, dispose of stock, or receive a loan repayment.¹²

Even in years none of those apply, the IRS recommends completing and keeping the form to hold a consistent running basis calculation.¹² Part I tracks stock basis, Part II tracks debt basis, and Part III handles the loss limitation. Reconstructing basis several years later, after records have thinned and accountants have changed, is one of the most expensive exercises in S corporation compliance. Keeping the form current each year is far cheaper than rebuilding it.

1
Office of the Law Revision Counsel. 26 USC 1366 – Pass-Thru of Items to Shareholders
2
Legal Information Institute. 26 USC 1367 – Adjustments to Basis of Stock of Shareholders, Etc.
3
Internal Revenue Service. Valid Shareholder Debt Owed by S Corporation
4
Federal Register. Section 1367 Regarding Open Account Debt
5
Justia Law. 26 USC 1367 – Adjustments to Basis of Stock of Shareholders, Etc.
6
Internal Revenue Service. S Corporation Stock Basis Ordering Rules
7
eCFR. 26 CFR 1.1367-2 – Adjustments to Basis of Indebtedness
8
Internal Revenue Service. S Corporation Stock and Debt Basis
9
Office of the Law Revision Counsel. 26 USC 7872 – Treatment of Loans With Below-Market Interest Rates
10
Office of the Law Revision Counsel. 26 USC 465 – Deductions Limited to Amount at Risk
11
Office of the Law Revision Counsel. 26 USC 469 – Passive Activity Losses and Credits Limited
12
Internal Revenue Service. Instructions for Form 7203 – S Corporation Shareholder Stock and Debt Basis Limitations