The IRS loan rules for retirement plans and family loans set two different traps. A loan from your 401(k) or similar employer plan stays tax-free only if it obeys every requirement in Internal Revenue Code Section 72(p): the borrowing cap, the five-year repayment period, level quarterly payments, and a commercially reasonable interest rate. A loan to a family member (or between an employer and employee, or a corporation and its shareholder) stays clean only if it charges at least the Applicable Federal Rate the IRS publishes each month, or fits within one of two dollar-limit exceptions. Miss either standard and the IRS creates taxable income out of thin air.
How Much You Can Borrow From a 401(k)
The borrowing cap is the lesser of $50,000 or half your vested account balance. There is a floor built in: if half your vested balance is under $10,000, you can still borrow up to $10,000, but never more than your total vested balance.1Office of the Law Revision Counsel. 26 USC 72 – Annuities; Certain Proceeds of Endowment and Life Insurance Contracts
The $50,000 ceiling also shrinks if you had a plan loan in the previous 12 months. It is reduced by the difference between your highest outstanding balance during that lookback period and the balance on the day the new loan is made. The rule prevents cycling loans at the maximum.
Repayment has to happen within five years, through substantially level payments made at least quarterly. The five-year clock stretches only if the loan is used to buy your principal residence; the IRS does not fix a maximum term for that exception, so your plan document controls.1Office of the Law Revision Counsel. 26 USC 72 – Annuities; Certain Proceeds of Endowment and Life Insurance Contracts
The interest rate must be commercially reasonable. Plan administrators typically use the prime rate plus one percentage point, and the IRS has consistently accepted that benchmark. You will sign a legally enforceable promissory note identifying the schedule, the rate, and the portion of your vested balance pledged as collateral. The interest you pay goes back into your own account, but if your collateral is elective deferrals (the usual 401(k) setup), that interest is not tax-deductible.
What Happens if You Break a Plan Loan Rule
Miss a payment, exceed the borrowing limit, or violate the level-amortization rule, and the IRS treats the loan as a “deemed distribution.” The outstanding principal plus accrued interest becomes taxable income in the year of the failure.2Internal Revenue Service. Deemed Distributions – Participant Loans
Your plan administrator will send you and the IRS a Form 1099-R. You report the taxable amount as ordinary income on Form 1040. If you are under age 59½, you also owe a 10% early withdrawal penalty on top of income tax, unless a narrow statutory exception applies.
The painful part: no cash actually left the plan, so nothing was withheld. You get a tax bill for the full amount without any money in hand, and the plan still expects you to keep repaying the loan. The obligation does not vanish just because the IRS taxed the balance.3Internal Revenue Service. Fixing Common Plan Mistakes – Plan Loan Failures and Deemed Distributions
Leaving Your Job With a Plan Loan Outstanding
Job separation is the most common trigger for plan loan problems. Many plans demand immediate repayment when you leave. If you cannot pay, the plan reduces your account balance by the loan amount. That is a plan loan offset, and it is treated as an actual distribution rather than a deemed one.4Internal Revenue Service. Plan Loan Offsets
The distinction matters because the offset can be rolled over. A qualified plan loan offset (QPLO), which happens specifically because of job separation or plan termination, gives you until your tax filing due date for that year, including extensions, to roll the offset amount into an IRA or another eligible plan. If you file an extension, that pushes the deadline to October 15 of the following year. You do not have to conjure the cash from the old plan; you can contribute an equivalent amount of your own money to the IRA and report the rollover. Miss the deadline and the full offset amount is taxable, plus the 10% penalty if you are under 59½.
Fixing a Plan Loan Mistake
Not every failure has to end in a tax hit. The IRS runs correction programs under the Employee Plans Compliance Resolution System (EPCRS) that can erase a deemed distribution if the error is caught and fixed properly.
For operational mistakes (a loan that exceeded the dollar limit, a missed quarterly payment) the plan sponsor can self-correct without filing anything or paying a fee, as long as it can show reasonable compliance procedures were in place and the failure was isolated.5Internal Revenue Service. Retirement Plan Errors Eligible for Self-Correction
Deeper problems require the Voluntary Correction Program (VCP), which involves a filing on Form 8950 and a user fee scaled to plan assets. A successful correction under either program removes the 1099-R reporting and wipes out the deemed distribution.3Internal Revenue Service. Fixing Common Plan Mistakes – Plan Loan Failures and Deemed Distributions If you are the participant, this is worth pushing your plan administrator to pursue rather than accepting the tax bill.
The Minimum Interest Rate on Family and Related-Party Loans
When you lend to a family member, an employee, or a shareholder at below-market interest, Section 7872 imputes the missing interest. The IRS pretends the lender gave the borrower enough money to pay market-rate interest, and pretends the borrower paid it back. Both fictional transfers have tax consequences.6Office of the Law Revision Counsel. 26 USC 7872 – Treatment of Loans With Below-Market Interest Rates
The minimum rate is the Applicable Federal Rate (AFR), published monthly by the IRS. The correct AFR depends on the loan’s term:
- Short-term (3 years or less): 3.59% annually as of March 2026
- Mid-term (over 3 years through 9 years): 3.93% annually
- Long-term (over 9 years): 4.72% annually
Charging even a fraction of a percent below the correct AFR triggers imputed interest on the entire shortfall. The rate that matters is the one published for the month the loan is made (for term loans) or the rate in effect during the year (for demand loans).
Demand Loans vs. Term Loans
A demand loan is any loan the lender can call due at any time. A term loan has a fixed repayment date. For demand loans, the imputed interest is recalculated each year using the short-term AFR then in effect, with the fictional transfers treated as occurring on December 31. For term loans, the AFR is locked in on the day the loan is made, and the entire present-value shortfall between the amount loaned and the discounted value of future payments is treated as transferred upfront. Front-loading creates a bigger immediate gift or compensation event but delivers rate certainty.
The Two Exceptions That Spare Most Family Loans
A below-market loan between family members is a gift loan. The imputed interest is a gift from lender to borrower, and the borrower is simultaneously treated as paying that interest back. The lender reports the imputed interest as taxable interest income. The borrower can only deduct the deemed interest payment if the loan proceeds were used for a deductible purpose, such as buying investment property.
Two exceptions in Section 7872 keep most family loans out of trouble.
The $10,000 De Minimis Exception
If the total outstanding loans between two individuals never exceed $10,000, the imputed interest rules do not apply at all. That covers the typical informal loan between relatives. The exception disappears if the borrower uses the money to buy income-producing assets like stocks or rental property.
The $100,000 Net Investment Income Cap
For gift loans where the total balance stays at or below $100,000, the imputed interest the lender must report is capped at the borrower’s net investment income for the year. If the borrower earned less than $1,000 in net investment income (interest, dividends, capital gains), the IRS treats that figure as zero, meaning no imputed interest at all.
In practice, a parent who lends a child $80,000 interest-free for a house down payment owes nothing in imputed interest as long as the child’s net investment income stays below $1,000. Once the aggregate balance crosses $100,000, this cap disappears and the full imputed interest rules kick in. The exception also drops away if tax avoidance is one of the principal purposes of the arrangement.6Office of the Law Revision Counsel. 26 USC 7872 – Treatment of Loans With Below-Market Interest Rates
Gift Tax Reporting on Family Loans
When the imputed interest on a gift loan exceeds the annual gift tax exclusion ($19,000 per recipient for 2026), the lender files Form 709. The imputed interest counts alongside any other gifts to the same person that year. Exceeding the exclusion does not automatically mean owing gift tax; it reduces the lender’s lifetime exemption and triggers the reporting requirement.8Internal Revenue Service. What’s New — Estate and Gift Tax
Loans From an Employer or a Closely Held Corporation
Below-market loans outside the family follow the same AFR mechanics but recharacterize the fictional transfer differently.
A below-market loan from an employer to an employee is treated as hidden compensation. The imputed interest is wages, reported on the employee’s Form W-2 and subject to payroll taxes; the employer takes a compensation deduction. The employee is then deemed to pay the interest back to the employer, producing taxable interest income on the employer’s side. The same $10,000 de minimis exception applies.
Corporation-shareholder loans get the harshest default treatment. When the corporation lends to a shareholder at below-market rates, the imputed interest is first treated as a dividend from corporation to shareholder. The shareholder reports dividend income, and the corporation generally gets no deduction. The shareholder is then deemed to pay that interest back to the corporation, creating corporate interest income. When the shareholder is the lender instead, the shortfall is treated as a capital contribution, followed by the corporation paying interest back to the shareholder. The tax treatment can differ for S-corporations, where distributions, basis, and pass-through income interact in ways that make professional advice worthwhile. The $10,000 de minimis exception applies to corporation-shareholder loans as well, but only if tax avoidance is not a principal purpose of the arrangement.
Documentation and Reporting
The single most important thing you can do with any related-party loan is put it in writing. A formal promissory note stating the principal, interest rate, maturity date, and repayment schedule is what separates a loan from a gift in the IRS’s eyes. Without documentation, the IRS can recharacterize the entire principal as a taxable gift or compensation on the date it was transferred.
Keep a consistent payment history to match. Sporadic or nonexistent payments are exactly what the IRS points to during an audit to argue neither side ever intended repayment. Even when the loan fits within the $10,000 or $100,000 exceptions, documentation is what protects the arrangement if it is questioned.
Reporting obligations depend on the type of loan:
- Gift loans: the lender reports imputed interest on Schedule B, and files Form 709 if the imputed interest plus other gifts to the same borrower exceeds $19,000 in 2026.
- Compensation loans: the employer reports imputed compensation on Form W-2 and reports the deemed interest income on its own return.
- Corporation-shareholder loans: the corporation reports interest income on its return, and if the corporation is the lender, may need to issue Form 1099-DIV for the deemed dividend. Business-entity lenders must also issue Form 1099-INT to the borrower if the imputed interest exceeds $600.9Internal Revenue Service. Topic No. 403, Interest Received