Avalanche vs. Snowball: Which Debt Payoff Method Wins?

Same debts. Same minimums. Same extra payment. Only the order of the extra dollar changes. Here is what both methods actually do to the same pile of debt — and why the extra payment matters far more than the order.

How each method works

The mechanic underneath both methods is identical. Each month, every balance grows by one month of interest, then payments hit:

new balance = old × (1 + APR ÷ 12) − payment

The only thing that changes is where the extra dollar goes. Avalanche sends every extra dollar to the highest APR first — the mathematically cheapest route. Snowball sends it to the smallest balance first — the fastest first win, which some people need to stay motivated.

Both methods on the same pile

Take the worked pile used throughout the Field Guide: $200 extra per month on top of the minimums, $710 total cash to debt each month. The $400 store card is both the smallest balance and the highest rate, so both methods kill it in about two months. After that they split — snowball attacks the small 19-percent card, avalanche attacks the large 24-percent card.

Same debts, same minimums — only the extra payment changes. Figures from the Planner's debt simulator.

The minimums-only trap

The $0-extra row is the quiet warning in the table: 82 months and $8,668 in interest on this pile. Minimums are priced to keep you paying, not to get you free. The first $50 of extra a month is the highest-value money in the whole table — it buys years off the timeline and thousands off the interest. Everything after that is still good, but the biggest win is simply getting off the minimums.

The motivation question

Math is not the whole story. Studies of real debt behavior find that many people are motivated by closing out entire accounts — the small win of a zero balance keeps them making the payment when the spreadsheet alone would not. That is the genuine case for snowball: if the fastest first win is what keeps the extra payment flowing every month, the “wrong” method you stick with beats the “right” method you abandon in month six. Pick the method you will still be using in month 20.

Run your own pile

The table above is one worked pile. Yours will differ — and the answer might too. List every balance with its APR and minimum, set a monthly extra you can actually sustain, and read the debt-free date out loud. The Planner's debt tab runs both methods on your real numbers and shows the months, the date, and the total interest side by side.

The extra dollar beats the method

Look at the columns, not just the rows. Getting off the minimums is the whole game: $200 extra saves about $5,000 in interest versus minimums-only, whichever method you pick. The method gap is real but small — and it shrinks as the extra payment grows.

Avalanche pulls away when one debt is much more expensive than the others, that expensive debt is not the smallest, and the extra payment is small. When the rates are clustered together, or the extra payment is large, the two methods almost tie. So the honest priority list is: first, get off the minimums with any extra you can sustain. Then pick the method you will actually stick with. The Planner's debt tab runs both on your real balances so you can see your own version of this table.