Both methods pay the minimum on every debt and throw all your extra money at one target debt until it’s gone, then roll that payment into the next one. The only difference is which debt you attack first, and that choice changes both the math and how likely you are to stick with it.
Debt snowball: smallest balance first
You list your debts from smallest balance to largest, ignoring interest rates entirely. Every extra dollar goes to the smallest one until it’s paid off, which usually happens fast. That quick win is the whole point: it’s motivation, not math.
Debt avalanche: highest interest rate first
You list your debts by interest rate instead, highest to lowest, and every extra dollar goes toward the most expensive debt regardless of its balance. This minimizes the total interest you pay over time, but the first “win” can take much longer to arrive if your highest-rate debt also has a large balance.
The real math, side by side
Say you have three debts and $400 a month in extra payment available:
- $500 balance at 8% APR
- $2,000 balance at 14% APR
- $6,000 balance at 22% APR
With the snowball, you order them $500, then $2,000, then $6,000. You pay off the $500 debt fastest, since it gets the full extra $400 on top of its own minimum. That’s a real payoff in the first month or two, then the freed-up payment rolls into the $2,000 debt, and finally the $6,000 one.
With the avalanche, you order them by rate instead: the $6,000 debt at 22% gets the extra $400 first, then the $2,000 debt at 14%, and the $500 debt at 8% gets paid off last, using only its minimum until the others are cleared.
The avalanche saves you more in total interest, because that 22% debt stops accruing extra interest sooner. The snowball costs a bit more overall, but it hands you a paid-off account within weeks instead of months.
So why does anyone choose snowball?
Because paying off debt is behavioral, not just mathematical. Seeing an account hit zero is genuinely motivating, and for a lot of people that motivation is what keeps the extra payments coming every month instead of quietly stopping after three.
A simple way to decide
- Choose avalanche if you’re disciplined with money regardless of quick wins, and want to minimize total interest paid
- Choose snowball if you’ve tried paying off debt before and lost motivation partway through
- Choose avalanche if your smallest debt and highest-rate debt are the same one, since there’s no tradeoff to make
- Either way, automate the extra payment so it doesn’t depend on remembering to send it manually