Income and Assets · Property, real and personal
Non-business bad debts
tax year · reviewed 2026-08-19 · Draft for N. O. review
- Real debt A valid, enforceable obligation to repay a fixed sum — not a gift or advance
- Not a business debt Not created in, or connected to, the lender's own trade or business
- Wholly worthless Completely uncollectible — not just harder to collect
The rule is short and the consequences are severe. A debt that is not connected with a trade or business and goes bad is not deductible as a bad debt at all: it is a short-term capital loss, however many years it was outstanding, deductible only against capital gains and the annual allowance. It is allowed only when the debt is wholly worthless, never in part. And if there was never a real debt — which is where most family loans end up — there is no deduction of any kind.
The rule
A nonbusiness debt is taken out of § 166(a) and recharacterised. For a taxpayer other than a corporation, the general bad debt deduction does not apply to a nonbusiness debt; where such a debt becomes worthless within the taxable year, the resulting loss is treated as a loss from the sale or exchange, during that year, of a capital asset held for not more than 1 year (IRC § 166(d)(1)(A), (B)). The holding period is imposed by the statute, so a fifteen-year-old loan produces a short-term loss.
What makes a debt nonbusiness. Any debt other than one created or acquired in connection with the taxpayer’s trade or business, or one whose worthlessness is incurred in that trade or business (IRC § 166(d)(2)). Whether a debt is nonbusiness is a question of fact, and the test is whether the loss bears a proximate relation to a trade or business the taxpayer is carrying on at the time the debt becomes worthless (Treas. Reg. § 1.166-5(b)).
And what the debtor does with the money is irrelevant. The regulation says so expressly: “The use to which the borrowed funds are put by the debtor is of no consequence” (Treas. Reg. § 1.166-5(b)). Lending to someone else’s business does not make the debt a business debt of the lender.
There must be a real debt. Only a bona fide debt qualifies — one arising from a debtor-creditor relationship based on a valid and enforceable obligation to pay a fixed or determinable sum of money. A gift or a contribution to capital is not a debt (Treas. Reg. § 1.166-1(c)). The fact that the debt is not yet due does not by itself prevent the deduction.
All or nothing. A loss on a nonbusiness debt is treated as sustained only if and when the debt has become totally worthless, and no deduction is allowed for a nonbusiness debt recoverable in part during the year (Treas. Reg. § 1.166-5(a)(2)). The partial-worthlessness route in § 166(a)(2) is closed to it.
The amount is basis, not face value. The deduction is measured by the adjusted basis provided in § 1011 for determining loss on a sale (IRC § 166(b)). For a cash-method lender, accrued but unpaid interest was never in income, has no basis, and produces nothing.
A worthless security is a different provision. Where a security that is a capital asset becomes worthless, the loss is treated as from a sale or exchange on the last day of the taxable year (IRC § 165(g)(1)) — which can convert a short holding into a long-term loss. A debt described in § 165(g)(2)(C) is expressly outside the nonbusiness bad debt rules (Treas. Reg. § 1.166-5(b), final sentence).
And there is a longer period to claim it. A claim for credit or refund relating to the deductibility of a worthless debt or security, or to its effect on a carryover, has a seven-year period of limitation in place of the ordinary one (IRC § 6511(d)(1)).
Current figures
| Item | 2026 |
|---|---|
| Character of the loss | Verified 2026-08-19IRC § 166(d)(1)(A), (B) — https://www.law.cornell.edu/uscode/text/26/166 |
| What is nonbusiness | Verified 2026-08-19IRC § 166(d)(2)(A), (B); Treas. Reg. § 1.166-5(b) — https://www.law.cornell.edu/cfr/text/26/1.166-5 |
| A real debt | Verified 2026-08-19Treas. Reg. § 1.166-1(c) — https://www.law.cornell.edu/cfr/text/26/1.166-1 |
| Partial worthlessness | Verified 2026-08-19Treas. Reg. § 1.166-5(a)(2) — https://www.law.cornell.edu/cfr/text/26/1.166-5 |
| Amount | Verified 2026-08-19IRC § 166(b) — https://www.law.cornell.edu/uscode/text/26/166 |
| The debtor’s use of the funds | Verified 2026-08-19Treas. Reg. § 1.166-5(b), closing sentences — https://www.law.cornell.edu/cfr/text/26/1.166-5 |
| Worthless securities | Verified 2026-08-19IRC § 165(g)(1), (2); Treas. Reg. § 1.166-5(b), final sentence — https://www.law.cornell.edu/uscode/text/26/165 |
| Refund period | Verified 2026-08-19IRC § 6511(d)(1)(A), (B) — https://www.law.cornell.edu/uscode/text/26/6511 |
| Annual capital loss allowance | Verified 2026-08-19IRC § 1211(b)(1), (2) — https://www.law.cornell.edu/uscode/text/26/1211 |
How it works in practice
The first question is not whether the debt is bad but whether it was a debt. A family advance with no note, no interest, no repayment schedule and no attempt at collection is a gift, and Treas. Reg. § 1.166-1(c) puts a gift outside § 166 entirely. Contemporaneous documentation — a written note, a stated rate, a schedule, and evidence of demands for payment — is what separates a deductible loss from nothing at all, and it has to exist before the loan goes bad.
The second is timing, and it cuts both ways. Because only total worthlessness counts, claiming too early is fatal: a debt still partly collectible produces no deduction in that year. Claiming too late loses the year. The seven-year period in § 6511(d)(1) exists precisely because worthlessness is hard to date, and it is the reason a late-discovered bad debt can still be claimed by amending a return that would otherwise be closed.
The third is what the loss is worth. A short-term capital loss offsets capital gains without limit and then ordinary income only up to the annual allowance, with the excess carried forward. A client expecting to deduct a 50,000-dollar failed loan against salary should be told early that this takes many years absent capital gains.
Scenario 1 — the loan that was a gift
Leila advances 60,000 dollars to her nephew to start a restaurant. There is no note, no interest rate and no repayment date; she never asks for payment. The restaurant fails in 2026.
There is no deduction at all. Treas. Reg. § 1.166-1(c) requires a bona fide debt arising from a debtor-creditor relationship based on a valid and enforceable obligation to pay a fixed or determinable sum, and provides that a gift is not a debt for § 166 purposes. What she has is a completed gift with transfer tax consequences and no income tax deduction. Had she taken a note at a stated rate with a schedule, and pressed for payment, the same 60,000 dollars would have been a short-term capital loss under § 166(d)(1)(B).
Scenario 2 — nine years, and still short term
Marcus lends 40,000 dollars to a friend in 2017 on a proper written note at a commercial rate. The friend becomes insolvent and the debt is wholly worthless in 2026. Marcus has 5,000 dollars of capital gains that year and a salary.
The debt is nonbusiness under IRC § 166(d)(2), so § 166(d)(1)(B) treats the 40,000-dollar loss as from the sale of a capital asset held not more than 1 year — short term regardless of the actual holding periodHow long a taxpayer owned an asset before selling it. It determines whether gain or loss on the sale is treated as long-term or short-term., despite nine years outstanding. It offsets his 5,000 dollars of capital gains in full, then the annual allowance against ordinary income, with the balance carried forward as a capital lossThe loss from selling an investment or other capital asset for less than its basis. The amount that can be used to offset other income in one year is limited. under § 1212(b). It will take more than a decade to absorb unless he realises capital gains.
Scenario 3 — the year that was wrong
Nadia lends 25,000 dollars to a small company. In 2025 the company defaults and she recovers 8,000 dollars; she deducts 17,000 dollars on her 2025 return. In 2026 the company is dissolved with nothing left.
The 2025 deduction is not allowable: Treas. Reg. § 1.166-5(a)(2) permits a nonbusiness bad debt loss only if and when the debt has become totally worthless, and no deduction is allowed for one recoverable in part during the year. The correct year is 2026, when the remaining 17,000 dollars became wholly worthless. If the 2025 position is corrected late, IRC § 6511(d)(1) gives seven years rather than the ordinary period to claim the 2026 loss.
Scenario 4 — ninety-five percent collected, and that's the problem
A taxpayer lent 100,000 dollars on a proper note — a bad debtA debt owed to the taxpayer that has become worthless. It's deducted differently depending on whether it arose from the taxpayer's business or was a personal loan. in the making. The borrower pays back 95,000 dollars over several years and then disappears, with no assets left to reach the remaining 5,000 dollars.
Treas. Reg. § 1.166-5(a)(2) draws the line at total worthlessness, not near-total worthlessness. If the last 5,000 dollars is genuinely uncollectible — not merely slow — what remains of the debt has become wholly worthless, and the loss is the unrecovered 5,000 dollars, not a percentage-based write-down of the original loan. The deduction turns on whether that last piece is truly gone, not on how much was already repaid.
Scenario 5 — filing the refund claim years later
A taxpayer’s accountant realises in 2026 that a debt actually became wholly worthless back in 2022, and no deduction was ever claimed for that year.
IRC § 6511(d)(1) gives seven years from the return’s due date to file a claim for credit or refund relating to the deductibility of a worthless debt, in place of the ordinary period. The taxpayer amends the 2022 return, attaching a statement establishing when and how the debt became wholly worthless. Because the extended period exists specifically for this situation, discovering it years late does not by itself close the door.
Short term is imposed, not observed. IRC § 166(d)(1)(B) deems the asset held not more than one year regardless of how long the loan ran.
Partial worthlessness is not available. Section 166(a)(2) allows a partial deduction only outside the nonbusiness rules.
The lender’s business, not the borrower’s, is the test. Treas. Reg. § 1.166-5(b) says the debtor’s use of the funds is of no consequence.
Unpaid interest has no basis for a cash-method lender. Section 166(b) measures the deduction by adjusted basis, and interest never taken into income has none.
How this has changed
The regulation still cites a repealed subsection. Treas. Reg. § 1.166-5(a)(1) denies a deduction “under either section 166(a) or section 166(c)”. Section 166(c) — the reserve method for bad debts — was repealed by Pub. L. 99-514 § 805(a) in 1986, and the bracketed repeal note now stands in its place in the statute. The regulation’s rule is unaffected, but one of the two provisions it names has not existed for forty years.
The same regulation still carries its pre-1977 holding periods. Paragraph (a)(2) reads “a capital asset held for not more than 1 year (6 months for taxable years beginning before 1977; 9 months for taxable years beginning in 1977)”. Those parentheticals are dead text preserved in a live rule — harmless, but a reminder that the regulation has not been touched in decades.
What has not changed is the effect of the short-term characterisation, and inflation has made it harsher. The annual capital loss allowance against ordinary income has stood at the same figure since 1986, so the practical value of a nonbusiness bad debt deduction has fallen steadily in real terms. The statute recharacterises the loss and a separate, unindexed provision then limits it.
The seven-year refund period is easy to overlook and rarely mentioned. Section 6511(d)(1) doubles and more the ordinary window for exactly the situation this topic produces — a loss whose correct year is disputed or discovered late.
Exam focus
Expect the character to be the whole question, with a long-held loan in the facts inviting a long-term answer. It is short term by statute.
Expect a family loan with no documentation, where the answer is that there was no debt.
Expect a partial recovery, testing whether you know the nonbusiness rules require total worthlessness.
Distinguish a worthless security from a bad debt: § 165(g) deems the sale on the last day of the year, which can produce a long-term loss on the same facts.
Check yourself
1. A taxpayer’s properly documented personal loan of 30,000 dollars, made eight years ago, becomes wholly worthless. What is the character of the loss?
Answer: A short-term capital loss. IRC § 166(d)(1)(B) treats a worthless nonbusiness debt as a loss from the sale of a capital asset held not more than one year, regardless of how long it was outstanding.
2. The same taxpayer recovers 40 percent of a different loan and expects the rest to be lost. May a partial deduction be taken?
Answer: No. Treas. Reg. § 1.166-5(a)(2) allows the loss only if and when the debt becomes totally worthless, and denies any deduction for a nonbusiness debt recoverable in part during the year.
3. A cash-method lender is owed 20,000 dollars of principal and 3,000 dollars of accrued interest, all worthless. What is deductible?
Answer: 20,000 dollars. IRC § 166(b) measures the deduction by adjusted basis under § 1011, and interest never included in income has no basis.
4. Does lending money to a friend’s business make the debt a business debt?
Answer: No. IRC § 166(d)(2) looks to the lender’s trade or business, and Treas. Reg. § 1.166-5(b) states that the use to which the debtor puts the funds is of no consequence.
5. A taxpayer discovers in 2026 that a debt actually became worthless in 2021. Is a claim still possible?
Answer: Potentially yes. IRC § 6511(d)(1) provides a seven-year period of limitation for a refund claim relating to the deductibility of a debt that became worthless, in place of the ordinary period.
Change log
- Initial draft. Sets out the IRC § 166(d)(1) recharacterisation of a nonbusiness bad debt as a short-term capital loss and the § 166(d)(2) definition, the Treas. Reg. § 1.166-1(c) bona fide debt requirement, the § 1.166-5(a)(2) all-or-nothing worthlessness rule, the § 166(b) basis measure, the § 165(g) treatment of worthless securities, and the seven-year refund period in § 6511(d)(1).
- Added a plain-language summary, a decision diagram of the three qualifying tests, glossary marks, and two typed scenarios (boundary, procedural) rounding out the scenario taxonomy.
Related topics
- Capital gains and losses (e.g., netting effect, short-term, long-term, mark- to market, virtual currency) 1.2.3.b
- Tax treatment of forgiveness of debt (e.g., Form 1099C, foreclosures, insolvency) 1.2.1.f
- Basis of assets (e.g., purchased, gifted or inherited) 1.2.3.c
- Sale or disposition of property including depreciation recapture rules and 1099A 1.2.3.a
- Investor versus trader 1.2.3.k