A 401(k) loan calculator compares interest paid to yourself against market growth while shares are out of the plan.
Solliciter un prêt sur son propre plan d'épargne retraite entreprise semble ingénieux : dispense d'enquête de solvabilité, taux préférentiels et paiement des intérêts réinjectés dans votre propre bas de laine. Pourtant, cette opportunité recèle deux écueils majeurs : l'épargne retirée n'est plus investie et manque les pics boursiers ; puis, les mensualités sont honorées avec votre salaire net d'impôt, aboutissant à une double imposition sur les intérêts.
Coût réel d'un emprunt 401(k)
Un prêt 401(k) se rembourse à vous-même avec intérêts, mais retire des dollars investis du marché. Si le fonds rend 8 % et le prêt 5 %, le coût d'opportunité net reste positif.
Changement d'emploi exige souvent remboursement rapide—distribution imposable si impossibilité de payer.
Comparez à un prêt personnel ou HELOC—règles employeur et frais varient.
Guide, exemples et méthodologie
How to use this 401(k) loan cost calculator
Model borrowing from your 401(k): loan amount, interest rate paid back to yourself, lost market growth on borrowed funds, job-change repayment risk, and alternative borrowing cost. US plans often allow loans up to 50% of vested balance (IRS limits apply).
Example (USD)
Item
Example
Risk
Loan
$20,000 from 401(k)
Not invested while outstanding
Opportunity cost
7% market return forgone
Can exceed loan interest
Job change
Balance due quickly
Potential tax + penalty if default
How we calculate
We compare ending balance if you left funds invested versus repaying a plan loan with stated interest, plus optional alternative loan APR. Plan rules, double taxation myths, and fees vary—read your SPD and talk to HR.
Common mistakes
Treating 401(k) interest paid to yourself as ‘free money’ while missing market gains.
Borrowing for discretionary spending instead of true emergencies.
Ignoring repayment if you leave the employer.
Reducing contributions while repaying the loan and missing the employer match.
IRS limits and plan rules (overview)
The IRS generally caps 401(k) loans at the lesser of $50,000 or 50% of your vested account balance (with additional rules for low balances). Not every plan offers loans; some allow two outstanding loans or restrict purpose. Maximum term is often five years except for primary residence. Your Summary Plan Description lists fees, default treatment, and whether you may continue contributions while repaying.
Job change and default risk
If you terminate employment with an outstanding loan, many plans require full repayment within 60–90 days. Unpaid balance may be treated as a distribution—ordinary income tax plus 10% early withdrawal penalty if under age 59½ (exceptions apply). That risk often exceeds the spread between plan loan rate and bank personal loan APR.
Alternatives to compare
Before borrowing from retirement, compare: taxable emergency fund, HYSA, 0% promo credit card (if payoff plan exists), home equity line (if secured debt is acceptable), or unsecured personal loan. Each avoids removing dollars from tax-advantaged compounding. Enter an alternative APR in this calculator to see if external borrowing costs less on a risk-adjusted basis.
Sometimes for short-term liquidity with stable employment, but opportunity cost and job-change repayment risk are real. Compare to a personal loan or emergency fund first using this calculator.
Que se passe-t-il en cas de perte d'emploi avec mon emprunt ?
Dans cette conjecture, l'administration fiscale exige le remboursement complet de l'encours sous de brefs délais. À défaut, le solde restant est requalifié en retrait anticipé imposable, assorti d'une pénalité légale automatique de 10 %.