What Is a 401(k) Loan and When Should You Use One?

When you need cash and you have a 401(k), it's tempting to borrow from it. You're borrowing your own money, after all — and you pay yourself back with interest. It sounds like a free loan. But 401(k) loans come with significant hidden costs that aren't obvious at first glance.

How 401(k) Loans Work

Most 401(k) plans allow you to borrow up to 50% of your vested balance, or $50,000, whichever is less. You repay the loan through payroll deductions over up to 5 years (longer for a primary home purchase). The interest rate is typically the prime rate plus 1–2%, and the interest goes back to your own account — not to a lender.

The Real Costs of a 401(k) Loan

• Opportunity cost: The borrowed money isn't invested and misses market growth. Borrow $20,000 when the market returns 8% that year and you miss $1,600 in growth.
• Double taxation on interest: You repay the loan with after-tax dollars, then pay taxes again on those same dollars in retirement.
• Risk of job loss: If you leave your job, the full loan balance is typically due within 60–90 days. If you can't repay, it's treated as a distribution — income taxes plus a 10% early withdrawal penalty.
• Contribution disruption: Many people stop contributing to their 401(k) while repaying the loan, losing both the employer match and compounding growth.

When a 401(k) Loan Makes Sense

• You have a genuine financial emergency and no other options (no emergency fund, can't qualify for other loans).
• You're confident you'll stay at your employer until the loan is repaid.
• The alternative is high-interest debt (credit cards at 20%+) that you can't pay off quickly.
• You can maintain your 401(k) contributions while repaying the loan.

Better Alternatives to a 401(k) Loan

• Emergency fund: The ideal solution — interest-free, no tax consequences.
• Personal loan: Often lower rates than credit cards, no impact on retirement savings.
• HELOC: Lower rates, but requires home equity and puts your home at risk.
• 0% APR credit card: For expenses you can pay off within the promo period.
• Roth IRA contributions: You can withdraw Roth IRA contributions (not earnings) at any time, penalty-free.

401(k) Loan vs. 401(k) Withdrawal

A 401(k) loan is almost always better than an early withdrawal. An early withdrawal triggers income tax on the full amount plus a 10% penalty — effectively costing 30–40% of whatever you take out. A loan avoids both, as long as you repay it. Only consider a withdrawal as a last resort in genuine hardship situations.