Debt Snowball vs Avalanche: The Same $18,400 of Debt, Both Ways

The avalanche method costs less; the snowball method gets finished more often. Run both against an identical $18,400 of debt on an identical $850 a month, and the avalanche saves about $610 in interest and finishes one month sooner. That is a much smaller gap than the argument around it suggests — and in exchange, the snowball clears your second debt four months earlier and your third two months earlier. Below are both runs, month by month, on the same five debts.

The head-to-head is the point. Almost every article on this compares the methods. Nobody publishes the two payoff tables.

The two methods in one line each

Avalanche: pay minimums on everything, put every spare dollar at the highest interest rate. Mathematically optimal.

Snowball: pay minimums on everything, put every spare dollar at the smallest balance. Psychologically optimal.

Both require the same thing to work: a fixed total payment that does not shrink as balances clear. That freed-up money rolls into the next debt. If it leaks into spending instead, neither method does anything.

The test case

Five debts, $18,400 total, and $850 a month available — $415 of minimums plus $435 extra.

This set is deliberately awkward. The smallest balance is also the highest rate, so both methods agree on the first target. The 0% medical bill is large and cheap, which is where they disagree most: the avalanche leaves it until last, the snowball clears it third.

The avalanche run

Order: store card (26.9%), card A (22.4%), card B (18.9%), personal loan (11.5%), medical (0%).

Total paid: $20,675. Interest: $2,275. Debt-free in 25 months.

The snowball run

Order: store card ($1,100), card B ($2,700), medical ($3,300), card A ($4,800), personal loan ($6,500).

Total paid: $21,285. Interest: $2,885. Debt-free in 26 months.

The gap, stated plainly

That last row is the honest way to frame this decision. Over 26 months, the snowball costs about $23 a month — roughly two coffees — for the experience of having your second debt gone four months sooner.

Note what did not happen. The snowball did not cost you years, and it did not cost you thousands. On this debt set the two methods land within one month and $610 of each other, because the largest balance and the highest rate were different debts and the effects partly cancelled. On a different debt set the gap would be wider — but it is worth checking your own numbers before assuming the choice is momentous.

Whether $23 a month is worth it depends entirely on one thing: whether you will still be doing this in month 20.

How to actually choose

Choose avalanche if you have stuck to a budget for several months already, you are motivated by the arithmetic itself, and your highest-rate debt is not so large that it will take a year to move. If your top-rate debt is a $12,000 card, the avalanche means twelve months with nothing cleared, which is where people quit.

Choose snowball if you have started and abandoned a payoff plan before, you have several small balances, or the number of bills arriving each month is itself the source of the stress. Removing three bills from your life in thirteen months is worth something real that the interest calculation does not capture.

The practical hybrid most people should use: clear anything under about $500 first regardless of rate — it costs almost nothing and buys immediate momentum — then switch to strict avalanche. In our test case that would have cleared the store card first anyway, then gone straight to card A, capturing most of both benefits.

Two rules that matter more than the method

1. Attack anything at triple-digit APR immediately. Payday loans and similar products sit outside this framework entirely. A 391% APR compounds against you faster than any repayment schedule can keep up with. That is an emergency, not an ordering decision.

2. Keep a small cash cushion while you pay down. Throwing every dollar at debt with $0 in savings means the next car repair goes straight back on the card you just cleared. A starter cushion first, then aggressive payoff — the ordering logic is in what to do with your first $1,000.

What makes the real difference

Notice that in both runs, the extra $435 a month did far more work than the ordering did. Avalanche versus snowball moved the outcome by $610 and one month. The extra payment itself moved it by years.

Run the same five debts with only the $415 of minimums and the result is 75 months — six years and three months — and $8,458 of interest. Against that, the $435 extra payment saves roughly $6,200 in interest and over four years of your life.

Put those two levers side by side and the priority is obvious:

The ordering question is a second-order optimisation worth $610. Finding the extra payment is the first-order one worth ten times that. People spend far more time on the first question than the second, which is exactly backwards.

So if you are not sure where the extra $435 a month would come from, that is by far the more valuable problem to work on. Start with a month where every dollar is assigned — the worked zero-based budget example — and a 30-day no-spend challenge is a reasonable way to find the first month’s worth.

If the payment is not there at all

If minimums alone are more than you can cover, neither method applies and you should not spend another minute on this comparison. That is a hardship situation with a different triage order, set out in the hardship triage order. Creditor hardship programs, reduced payment plans and interest freezes exist, and they work considerably better when you call before you miss a payment rather than after.

Setting it up this week

1. List every debt: balance, APR, minimum. Get the APRs from statements, not memory.
2. Work out your true total monthly payment and commit to holding it constant.
3. Pick an order — avalanche, snowball, or clear-under-$500-then-avalanche.
4. Automate the minimums. Make the extra payment manually, on the same day each month, so you see it happen.
5. Track the total balance monthly. One number, on one line. That line going down is the thing that keeps people going.

Then stop optimising and start paying. The best method is the one still running in month 20.

Educational information only, not personalized financial advice. Payoff figures are approximate amortisation estimates on the illustrative debts shown and will differ from your own; your actual results depend on your rates, minimum payment formulas and payment timing. Last reviewed 26 September 2026.