Avalanche vs Snowball Method: A Worked Example

Updated October 27, 2026

Avalanche and snowball do not change the minimum you owe on each debt. They only choose where extra money goes, including the minimum that gets freed when a balance hits zero. Avalanche points that money at the highest APR. Snowball points it at the smallest balance. If those two sorts produce the same list, the plans are identical and the names are just labels.

The debts in the example

These are the three rows prefilled on the calculator, with the extra payment set to $0. Minimums stay at the dollar amount in the table. They do not fall as a percent of the balance. APRs do not change. Every month is paid on time.

Attack order is not the same thing as the month a balance reaches zero. Avalanche's list is Credit Card 1, then Credit Card 2, then the loan, because 25% is the highest rate. Snowball's list is the loan, then Credit Card 2, then Credit Card 1, because $1,000 is the smallest balance. With no extra payment, both plans pay only the minimums until something is paid off, so the lists do not matter yet.

Month 1 is the same either way

Interest is the starting balance times APR divided by 12.

• Credit Card 1: 8,000 × 0.25 / 12 = $166.67 of interest. The $200 minimum covers that and $33.33 of principal, leaving $7,966.67.
• Credit Card 2: 4,000 × 0.15 / 12 = $50.00 of interest and $50.00 of principal, leaving $3,950.00.
• Personal loan: 1,000 × 0.075 / 12 = $6.25 of interest and $43.75 of principal, leaving $956.25.

You pay $350. Of that, $222.92 is interest. The calculator keeps fractions of a cent internally and rounds when it prints a total, which is why 166.67 + 50.00 + 6.25 lands on $222.92.

Where the plans split

The loan's own $50 minimum clears it in month 22 under both methods. That month's payment is $321.62 rather than $350, because the loan's last bill is only the remaining balance plus interest, and interest across the three debts is $183.84. At the end of month 22 the loan is gone and the two cards are still open: about $7,081.59 on Credit Card 1 and about $2,742.85 on Credit Card 2.

The loan's $50 minimum joins the extra pile in month 23, not in month 22. Avalanche sends that $50 to Credit Card 1. Snowball sends it to Credit Card 2, the smaller balance that is still open. From that month on, the cards diverge.

Snowball deletes the smaller card 13 months sooner. The expensive card then lingers one month longer, and total interest is $255.78 higher. On the calculator those interest totals round to the nearest dollar, so the page shows $8,802 and $9,058, and the savings banner shows $256.

The gap is small because the only "extra" in this run is the $50 freed in month 23. Set the extra payment to $100 from the first month, on top of the $350 of minimums, and the aim matters immediately.

Avalanche costs $861.47 less interest and finishes two months sooner than snowball. Against the avalanche plan with no extra payment (63 months and $8,801.76), the $100 extra saves $3,665.70 of interest and 22 months. The screen rounds those interest figures to $5,136, $5,998, and a savings banner of $861.

When the results match

If the smallest balance also has the highest APR, and the next-smallest has the next-highest APR, both methods build the same list. Extra money and freed minimums hit the same debt. This set does that, with an extra payment of $150:

Both methods finish in 35 months and charge $2,541.02 of interest. The store card is paid off in month 6, the Visa in month 23, and the auto loan in month 35. Drop the extra payment to $0 and both methods take 53 months and $4,989.74 of interest. The $150 is doing the work. The method name is not.

Chronological payoff can still differ from the attack list when you are only paying minimums. In that $0 run the store card, which is first in line, is not the first balance to hit zero, because $35 barely covers a 27.99% rate on $900. The comparison that matters is the total interest and the final month, which match. Enter the three rows and both strategies if you want to see the banner say the costs are nearly the same.

Choosing when the dollars are close

A few hundred dollars over five years is real money, and it is also small next to a missed month. If the banner on your own debts is a wide gap, avalanche is the cheaper order under these rules. If the banner is almost flat, the useful question is which list you will still follow after a tight month. This page cannot see that. It also cannot see a promo rate that ends, a fee to move a balance, or a minimum that shrinks. Those belong in the balance-transfer guide and the extra-payment table.

Related: how the month loop works, and what an extra $50 to $200 changes.