Windfall Debt Payoff Optimizer
Example: Windfall amount to apply to debt: 3000 $ · High-rate debt balance: 8000 $ · High-rate debt APR: 23.99 % · Low-rate debt balance: 2500 $ · Low-rate debt APR: 8.5 % · Extra monthly payment after windfall: 200 $ · Projection horizon: 60 months
| Extra interest saved by paying high-rate first | $1,035 |
| Total interest: high-rate-first strategy | $1,069 |
| Total interest: low-rate-first strategy | $2,104 |
| Cost of the emotional payoff choice | $1,035 |
Worked example
A $3,000 tax refund applied to the $8,000 card at 23.99% (versus the $2,500 loan at 8.5%) saves roughly $480 more in interest over a 60-month horizon compared to clearing the smaller, lower-rate loan first. The emotional choice to eliminate the smaller debt costs $480 in this scenario — a meaningful but not catastrophic difference. If that psychological win helps you stay motivated and not add new debt, it may still be worth it. The goal of this tool is to make the trade-off explicit.
Frequently asked questions
What if the windfall is large enough to pay off both debts?
If the windfall covers all debts, congratulations — allocate as much as needed to clear both completely and invest the rest. This calculator is designed for the more common scenario where the windfall pays down, but does not fully eliminate, the debt stack.
Should I pay off debt or put the windfall into an emergency fund first?
Financial planners generally recommend maintaining a 1–3 month emergency fund before aggressively paying down non-emergency debt. If you have zero savings and $8,000 in debt, applying the entire windfall to debt leaves you vulnerable to new debt if an emergency arises. A common approach: fund 1 month of expenses in a savings account, then apply the rest to the highest-rate balance.
Is there a tax on windfalls like bonuses or inheritance?
Employment bonuses are taxed as ordinary income. Inheritances are generally not federally taxed for the recipient (the estate may owe estate tax), though some states have an inheritance tax. Capital gains from selling assets are taxed at capital gains rates. Consult a tax professional if you are unsure of the after-tax amount before applying it to debt.
Does applying a lump sum to debt hurt my credit score?
Paying down credit card balances reduces your credit utilization, which is the second-largest factor in most credit scores — so it typically helps. Paying off an installment loan in full may slightly lower your score temporarily (loss of account diversity or active installment account), but the effect is usually small and short-lived.