Debt snowball vs avalanche: how to pick a method and track your payoff

The two methods in one paragraph each

The debt snowball orders your debts from smallest balance to largest. You pay the minimum on everything and put every extra dollar on the smallest balance. When it is gone, its payment rolls into the next smallest, so the amount you throw at each target keeps growing.

The debt avalanche orders your debts from highest interest rate to lowest. The mechanics are identical, minimums everywhere and the extra on one target, but the target is the most expensive debt rather than the smallest. Mathematically it always costs the same or less in interest. The question is whether you will stick with it.

A worked example with three debts

Say you owe three debts and can put $600 a month toward them. The minimums add up to $270, which leaves $330 a month of extra payment to aim at one target.

The snowball attacks the store card first, then the personal loan, then the credit card. The avalanche attacks the credit card first, because 24.9% is the highest rate, then the store card, then the loan. Run both month by month, with interest charged on each balance before that month’s payments, and you get this:

The avalanche saves about $430 and one month here. The snowball gives you a paid-off account in month 3 instead of month 14. For comparison, paying only the $270 of minimums would take about 87 months and roughly $6,944 in interest. The method matters less than the extra $330.

Your numbers will differ. The gap between the methods grows when your smallest debt also has the lowest rate and your biggest debt has the highest, and it shrinks to nothing when the smallest debt is also the most expensive, because then both methods pick the same order.

How to choose

• Pick the avalanche if the rate gap between your debts is wide (say, a 25% card next to a 6% loan) and you are motivated by the total you save.
• Pick the snowball if you have tried before and stalled, or if you have several small balances you could clear within a few months. Closing accounts early is a real reason people keep going.
• If the two orders are the same for your debts, stop deciding and start paying.
• A hybrid is fine: clear one or two tiny balances first for momentum, then switch to highest rate.

Whichever you pick, write the order down once and do not reshuffle it every month. Most plans fail from drift, not from choosing the wrong method.

What to track every month

A payoff plan only works if you can see it moving. For each debt, keep the balance, the rate, the minimum, and a log of every payment you make. The useful detail is how each payment splits between interest and principal. In month one of the example, about $107.90 of the credit card payment is interest. Watching that number fall is the clearest sign the plan is working.

1. 01On payday, pay every minimum first.
2. 02Send the full extra amount to the current target debt, the same day if you can.
3. 03Log each payment with its date and amount, then the new balance from the statement.
4. 04Note how much of the payment went to interest. If it is not falling, check for new charges or a rate change.
5. 05When a debt hits zero, add its whole payment (minimum plus extra) to the next target.

Mistakes that stall a payoff plan

• Still using the card you are paying off. New charges quietly undo the extra payment.
• No small cash buffer. One car repair goes back on the card and the plan feels broken. A few hundred dollars set aside first prevents that.
• Missing the end of a 0% promotional rate. Write the end date next to the debt; the rate that follows can jump it to the top of an avalanche.
• Treating the plan as a one-time calculation. Balances, rates and income change, so check the order each quarter.