Debt Snowball Payoff Calculator
The debt snowball method pays off the debt with the smallest balance first, then rolls that payment onto the next-smallest balance. Because it clears whole debts quickly, it builds momentum and can be easier to stick with, even though it usually costs a little more interest than the avalanche method. This calculator simulates up to three debts month by month: it accrues interest, applies minimum payments, and directs your extra payment to the smallest balance. It returns the months to be debt-free and the total interest paid. Enter each debt's balance, annual rate, and minimum payment, plus any extra monthly payment.
Snowball method
Each month: interest = balance * (annual rate / 12)
Pay minimum on every debt, plus extra to the smallest balance
When a debt clears, roll its payment to the next smallest balance
Repeat until all balances reach zero
Total interest = sum of all interest accrued
Snowball orders debts strictly by balance, smallest first, which clears individual debts quickly for motivation even though it is not the lowest-interest ordering.
Payoff context
- Snowball delivers quick wins; avalanche minimises total interest.
- Every extra dollar shortens the payoff and cuts total interest.
- Set unused debts to zero balance to model fewer than three debts.
- If a minimum is below the monthly interest, that debt will not pay off.
- Results assume fixed rates and minimums for the whole period.
Debt snowball: frequently asked questions
What is the debt snowball method?
The debt snowball method directs every spare dollar to the debt with the smallest balance first, while paying the minimum on the rest. When the smallest debt is cleared, its payment rolls onto the next-smallest balance. The early wins are designed to build momentum and motivation.
How does this differ from the avalanche method?
The avalanche method targets the highest interest rate first to minimise total interest. The snowball method targets the smallest balance first for psychological momentum. Snowball usually pays slightly more interest but can be easier to stick with.
How is the payoff time calculated?
The calculator simulates month by month. Each month, interest accrues on every balance, minimum payments are applied, and any extra payment plus freed-up minimums go to the smallest remaining balance. It counts the months until all balances reach zero.
What if a minimum payment is too low?
If a debt's minimum does not cover its monthly interest, the balance can grow and the plan may never finish. The calculator caps the simulation and reports that the debts do not pay off, indicating you need a larger payment.
Are the results exact?
They are exact for the inputs given, assuming fixed rates, fixed minimums, and the extra payment applied every month. Real accounts may have changing rates, fees, or variable minimums, so treat the output as a close planning estimate.
Official sources
- U.S. Consumer Financial Protection Bureau: consumerfinance.gov.
- U.S. Securities and Exchange Commission: Investor.gov.
Reviewed by the CalculatorHub team, edited by James Graham, 17 June 2026. See our methodology.