Why doesn't my solo 401(k) offer a loan option?

Most brokerage-provided solo 401(k) plans do not include a loan provision in their plan documents. The loan feature must be built into the plan from the start, usually through an open-architecture plan document. You may be able to restate the plan with a provider that includes it.

Can You Borrow From a Solo 401(k)? Loan Rules, Limits, and the Catch

Q: Can you borrow from a solo 401(k)?

Yes, if your solo 401(k) plan document includes a participant loan provision. You can borrow the lesser of $50,000 or 50% of your vested balance, tax-free and penalty-free as long as you repay on schedule. SEP IRAs do not allow loans at all.

Q: What is the maximum solo 401(k) loan amount?

The lesser of $50,000 or 50% of your vested account balance. A 12-month lookback rule reduces what you can borrow by your highest outstanding loan balance during the prior year, even if that loan is now paid off.

Q: What happens if you default on a solo 401(k) loan?

The outstanding balance becomes a deemed distribution: taxable as ordinary income in that year, plus a 10% early withdrawal penalty if you are under 59 and a half. You cannot fix it by catching up after the cure period expires.

Guides · Updated October 2026

A friend who runs a one-person consulting shop called me earlier this year with a cash problem you can probably picture: a $28,000 equipment bill due in three weeks, a bank line the lender would not renew, and $140,000 sitting in his solo 401(k). He was ready to take a taxable distribution and eat the penalty. Can you borrow from a solo 401(k)? That one question saved him from one of the worst financial moves a self-employed person can make.

Can you borrow from a solo 401(k)? The rules as written

Yes, if your plan document allows it. The IRS treats a solo 401(k) participant loan like any other 401(k) loan, and the terms are specific:

Maximum: the lesser of $50,000 or 50% of your vested balance.
Repayment: at least quarterly, over a term of up to five years. Buying a primary residence can stretch the term longer, if the plan allows it.
Interest: the plan must charge a reasonable rate, usually the prime rate plus about 1%. The twist: you pay that interest back into your own account, not to a bank.
No credit check, no underwriting. You are borrowing from yourself.

A loan structured this way triggers no income tax and no 10% early withdrawal penalty. It is not a distribution. My friend borrowed $30,000 for the equipment, kept making quarterly payments, and the interest went back into his own plan. That part is as clean as it sounds.

The math: what you can actually borrow

Run the formula against your own balance before you get excited:

Vested balance $140,000 → 50%	$70,000
$50,000 cap vs $70,000	lesser is $50,000
Maximum loan	$50,000
Vested balance $60,000 → 50%	$30,000
Maximum loan	$30,000

Simple enough. Now here is the rule that trips people up. The IRS applies a 12-month lookback: your available loan amount is reduced by your highest outstanding loan balance during the previous 12 months, even if that loan is fully paid off. Borrowed $20,000 last March and repaid it in full by December? Your maximum this year is $30,000, not $50,000. People discover this rule at exactly the moment they need the full amount.

Your plan may not allow this at all

I held this back because it is the real answer for most people. The solo 401(k) loan is a plan feature, not an automatic right. Your plan document must include a participant loan provision, and most brokerage-provided solo 401(k) plans simply do not. The free plans from the big discount brokerages are built to take contributions and invest them, not to administer loans.

Getting the loan feature usually means setting up the plan through an open-architecture provider whose plan document includes the loan provision from the start. If you already have a plan that lacks it, you can restate the plan document, but that is real paperwork, not a checkbox. I know this sounds like fine print designed to sell plan services, and I wish it were not true, but I have watched too many people assume the loan was available and learn otherwise with a deadline already ticking.

The default trap. This is the one that costs people real money. If you miss payments and do not cure the default within the grace period, the outstanding balance becomes a deemed distribution: taxable as ordinary income that year, plus a 10% penalty if you are under 59 and a half. The tax-free loan turns into the worst kind of taxable event, and there is no undo button once the cure period expires. Only borrow what your cash flow can actually repay.

Two quieter costs worth knowing

First, the double-tax wrinkle. You repay the loan with after-tax dollars, and you will pay income tax again when you eventually withdraw that money in retirement. The principal is not double-taxed (you got it tax-free), but the interest portion effectively is. Nobody explains this at signup.

Second, the opportunity cost of the borrowed money. The $30,000 you pull out is not invested while it is out. At 7% average market growth over five years, that is roughly $12,000 of growth you did not get, against the interest you paid yourself back. Borrowing from yourself is cheap, but it is not free.

Why this decides the solo 401(k) vs SEP IRA question

Here is where this gets practical for anyone choosing between the two plans. A SEP IRA cannot make loans to participants, period. No provision, no workaround. If you are a self-employed person choosing between a solo 401(k) and a SEP IRA, the loan feature is one of the few differences that is genuinely one-sided. Higher contribution limits at lower incomes matter too, but the loan is the one thing a SEP IRA simply cannot match, at any income, under any interpretation.

If your business income is lumpy enough that you might need bridge cash, pick the solo 401(k) for the loan feature before you even run the contribution math. Just confirm the plan document includes the loan provision before you fund the account, because funding a plan that lacks it and discovering the gap later is the exact mistake my friend almost made.

Choosing between a solo 401(k) and a SEP IRA?

Run your own income through both plans and see the difference.

Run your own numbers with the free calculator

Frequently asked questions

Can you borrow from a solo 401(k)?

Yes, if your plan document includes a participant loan provision. You can borrow the lesser of $50,000 or 50% of your vested balance, tax-free and penalty-free as long as you repay on schedule. Most brokerage-provided solo 401(k) plans do not include this provision.

What is the maximum solo 401(k) loan amount?

The lesser of $50,000 or 50% of your vested balance, reduced by your highest outstanding loan balance during the prior 12 months. Repayment must be at least quarterly over a term of up to five years, longer for a primary residence if the plan allows it.

What happens if you default on a solo 401(k) loan?

The outstanding balance becomes a deemed distribution, taxable as ordinary income in the year of default, plus a 10% early withdrawal penalty if you are under 59 and a half. Catching up after the cure period expires does not undo it.

Does a solo 401(k) loan require a credit check?

No. You are borrowing from your own account, so there is no underwriting and no credit check. The interest, typically around the prime rate plus 1%, goes back into your own plan rather than to a lender.

Can you borrow from a SEP IRA instead?

No. SEP IRAs cannot make loans to participants. The loan feature is available only through a solo 401(k) whose plan document includes the participant loan provision, which makes it one of the few genuinely one-sided differences between the two plans.

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