Debt Payoff Strategies: Snowball vs Avalanche
Two strategies dominate debt payoff advice. Avalanche attacks the highest interest rate first, minimizing total interest. Snowball attacks the smallest balance first, scoring quick wins for motivation. The math favors one; psychology often favors the other.
This guide runs the numbers so you can choose with eyes open.
The avalanche: mathematically optimal
List debts by interest rate, pay minimums on all, throw every extra dollar at the highest rate. When it dies, roll its payment into the next highest.
Every dollar of extra payment kills the most expensive debt first, so total interest is minimized and payoff is fastest for a given payment.
Example: $5,000 at 24% and $8,000 at 12%. Avalanche clears the 24% card first, saving hundreds versus the reverse order.
The snowball: psychologically powerful
List debts by balance, attack the smallest first regardless of rate. Each cleared debt frees its minimum payment and delivers a visible victory.
Studies find people stick with snowball longer. The best strategy is the one you actually follow for years.
The cost of snowball is the extra interest from delaying high-rate debts; often a few hundred dollars on typical balances.
Running your numbers
Compute months to payoff for one debt: with balance B, monthly rate r and payment P (above the interest), months = -ln(1 - rB/P) / ln(1+r).
If your payment barely covers interest, the balance never falls. The calculator flags this: any payment must exceed the monthly interest charge.
For multiple debts, model each separately, then add the freed payments as each debt clears.
Rules that beat both strategies
Stop adding new debt first; payoff math assumes balances only shrink. Automate payments so willpower is not required.
Build a small emergency buffer ($500-$1,000) before aggressive payoff, or the next surprise goes back on the card.
Negotiate rates: a single phone call can cut a card rate several points, which beats any strategy refinement.
Want the number right now? Run the matching calculator.
Try the Loan Payoff calculatorFrequently asked questions
Snowball or avalanche: which is better?
Avalanche costs less mathematically; snowball wins on motivation. Pick the one you will sustain.
How do I compute months to payoff?
Using the loan payoff formula with your balance, rate and payment; the calculator does it instantly.
What if my payment only covers interest?
The debt never shrinks. You must pay more than the monthly interest charge to make progress.
Should I save or pay debt first?
Keep a small emergency buffer, then attack high-interest debt before investing.
Does paying extra really help?
Enormously. Extra payments go to principal and cut all future interest on that amount.
Can I negotiate my rate?
Often yes. Issuers regularly grant reductions to customers who ask and have decent history.