Both methods work the same way mechanically: pay the minimum on every debt, then throw every spare dollar at one target. When that target is cleared, its entire payment rolls into the next one. The payment total never drops, so each debt falls faster than the last.
The only thing they disagree on is which debt to target first.
- Avalanche: highest interest rate first. Mathematically optimal — costs the least.
- Snowball: smallest balance first. Clears individual debts sooner.
The interesting question isn't which is cheaper — avalanche always is. It's how much cheaper, because that's what tells you whether the trade-off is worth it.
A worked comparison
Say you have two debts and $575 a month to put toward them.
| Debt | Balance | APR | Minimum |
|---|---|---|---|
| Car loan | $1,500 | 6% | $50 |
| Credit card | $9,000 | 23% | $225 |
The two methods disagree here: the card has the punishing rate, but the car loan is the small balance.
Avalanche — card first
Pay $50 on the car, put the remaining $525 on the card. The card clears in roughly 21 months. The car loan, meanwhile, has been quietly shrinking on minimums and takes about one more month once the full payment rolls onto it.
Roughly 22 months, about $2,100 in total interest.
Snowball — car first
Pay $225 on the card, put the remaining $350 on the car. The car clears in about 4 months — a quick, visible win. Then the full $575 attacks the card, which has grown in the meantime at 23%.
Roughly 22–23 months, about $2,450 in total interest.
What that gap actually tells you
Most people expect the avalanche to win by a mile. At typical household balances it usually doesn't — a few hundred dollars over roughly two years.
The gap widens sharply in two situations:
- A wide rate spread. Two debts at 6% and 8% barely differ in order. A 4% student loan against a 27% store card is a different story.
- Large balances. A few hundred dollars of difference on $10,000 of debt becomes a few thousand on $60,000.
If every one of your debts sits within a few points of the others, the ordering barely matters. Pick whichever you'll stick with and get on with it.
Compare both methods with your actual balances
Open Debt Payoff Calculator →Why the "worse" method often wins in practice
Avalanche is optimal on a spreadsheet. Spreadsheets don't give up in month five.
Research into how people actually repay debt has consistently pointed the same direction: those who eliminate small balances early are more likely to stay with the plan. Closing an account is concrete and final in a way that "the big balance went from $9,000 to $8,100" simply isn't, and that sense of progress is what carries people through month eleven.
Framed as a decision, it's straightforward: a snowball plan you finish beats an avalanche plan you abandon. The $350 only exists if you make it to the end.
There's also a practical benefit people overlook. Clearing a debt removes its minimum payment from your obligations permanently. If your income is unstable, having fewer separate bills due each month is real breathing room, not just a psychological trick.
The hybrid most people should probably use
You don't have to pick a side.
- Clear anything trivially small first. A $200 balance isn't a strategy decision — pay it, close it, reduce your number of bills.
- Then go strict avalanche on what remains. Once the clutter is gone, order by interest rate and let the math work.
This captures most of the early motivation and most of the interest saving. If one debt is dramatically more expensive than everything else — a payday loan, a 29% store card — put it first regardless of balance. At those rates nothing else is close.
Before you start either plan
- Keep a small cash buffer. Somewhere around $1,000–$2,000. With nothing set aside, the next car repair goes straight back on a card and you've undone months of work.
- Take any employer retirement match first. A full match is an immediate return on your money that no payoff strategy beats. Contribute enough to capture it before going all-in on debt.
- Check your actual APRs. Not the number you remember — the one on your current statement. Promotional rates expire and card rates change.
- Confirm there's no prepayment penalty. Rare on credit cards, occasionally present on personal and auto loans.
- Automate the minimums. One missed payment can trigger a penalty APR that costs more than your entire choice of method.
The part that matters more than the method
Neither method changes your interest rates or your income. What drives the timeline is the size of the extra payment.
In the example above, $575 a month cleared $10,500 of debt in under two years. At $400 a month it stretches past three years and the interest climbs substantially. Finding another $100 a month moves the needle far more than optimising the order ever will.
So: pick the method you'll actually follow, then put your energy into making the extra payment bigger. That's the lever.
Related: Compound Interest: Why the Math Rewards Patience — the same mechanics that make debt expensive make savings grow. And How to Read a Pay Stub if you're working out how much you can realistically free up each month.