Two payoff methods dominate every debt plan, and they differ in exactly one choice: which debt to attack first. Snowball targets the smallest balance first, clearing debts quickly for fast wins. Avalanche targets the highest interest rate first, minimizing total interest. Both use the same monthly money: every minimum plus one extra payment, with freed minimums rolling into the next target as debts die. Both work. The question is which trade-off fits you: motivation now, or money saved overall.
List every debt by balance, smallest first. Pay every minimum as usual. Send the extra payment, plus the minimum payments of debts already paid off, to the smallest balance until it is gone. Then move the whole pool to the next smallest balance. The first payoff comes fast when a small debt exists, and each cleared debt is visible proof of progress. That visible progress is the entire point: people who see debts disappearing tend to keep going, and a plan that survives beats a perfect plan that gets abandoned.
List every debt by APR, highest first. Pay every minimum as usual. Send the extra payment, plus the freed minimum payments, to the highest APR debt until it is gone, then move to the next highest rate. In the calculator's model, avalanche never costs more interest than snowball on the same debts and the same monthly money, because expensive interest is removed first. The catch is patience: if the highest APR debt is also the largest balance, the first payoff can take a long time, and months without a visible win test motivation.
Three debts: Card A $5,000 at 24 percent with a $150 minimum, Card B $2,000 at 18 percent with a $60 minimum, and Loan C $8,000 at 7 percent with a $200 minimum, plus an extra $300 per month. Both methods take 24 months to become debt-free. Snowball costs $1,997.30 in total interest, while avalanche costs $1,882.70, so avalanche saves $114.60. The gap is small because the balances are small and the extra payment is large relative to them. When the math gap is this small, motivation is a legitimate tiebreaker: $114.60 is a reasonable price for a method you will actually finish.
Change the shape of the problem and the answer changes. Take Card X $8,000 at 27 percent with a $200 minimum and Card Y $3,000 at 12 percent with a $75 minimum, plus an extra $250 per month. Snowball takes 28 months with $3,687.48 of total interest. Avalanche takes 27 months with $2,941.34. Avalanche saves $746.14 and finishes one month sooner. The wider the APR spread and the larger the high rate balance, the more avalanche wins: a 15 point gap on $8,000 is not a rounding error.
Start with the APR spread. If the rates are close and the balances are small, pick the method you will stick with, and snowball's quick wins are a real feature. If one debt carries a rate far above the rest, avalanche's saving is usually too large to ignore. A hybrid also works: clear one tiny debt by snowball for the motivational win, then switch to avalanche for the rest. Whatever you pick, two rules apply. First, never let a minimum payment fall below one month of interest on any debt, or that balance grows every month instead of shrinking, and the page shows a warning in that case. Raise the payment above the monthly interest before anything else. Second, keep a small emergency buffer first if you have none, so the next surprise does not go straight back onto a card and undo the plan.
Yes. The target order is a choice, not a contract. Pay minimums on everything, then point the extra payment and freed minimums at whichever debt you choose next. Switching from snowball to avalanche after the first quick win is a common and sensible hybrid.
The plan still works. Each debt is paid at its minimum, and freed minimums roll into the next target debt as debts are paid off. Adding even a small extra payment usually cuts months off the plan and saves interest, so add what you can, even $25 or $50 a month.
Many advisers suggest a small starter buffer first, enough to cover a minor surprise without new borrowing, then full focus on the debts. Once the debts are gone, build the buffer up to several months of expenses.
Paying down balances helps utilization, which is one factor in credit scoring, and the effect is larger on cards that are close to their limits. Order matters less than consistency: on-time payments every month and falling balances move the score in the right direction under either method.
This page explains how the math works. It is not financial advice.
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