Interest saved by paying highest-rate debt first versus smallest-balance first

Avalanche vs Snowball — Two Strategies, Same Payment

Avalanche and snowball are debt payoff strategies that differ only in ordering. Avalanche attacks the highest-interest debt first while making minimums on others. Snowball attacks the smallest balance first regardless of rate. Both strategies use the same total monthly payment — only the allocation differs. Avalanche saves more interest mathematically because it kills the most expensive debt first. Snowball provides faster psychological wins because small balances close quickly, reinforcing momentum.

How Much Does Avalanche Actually Save

The savings depend on the gap between highest-rate and average-rate debt. A portfolio with 20,000 total where the highest rate is 24% and average is 15% sees larger savings than one where highest is 18% and average is 15%. Typical avalanche savings range from 500-3,000 on portfolios under 30,000. Larger portfolios with wider rate spreads can save 5,000-15,000. The calculator shows the specific savings for your actual debt profile.

Worked Example for Mixed Debt Portfolio

Total debt 20,000. Highest rate 24%. Average rate 15%. Monthly payment 500. Avalanche total interest approximately 6,200 over 44 months. Snowball total interest approximately 7,900 over 51 months. Avalanche saves 1,700 and finishes 7 months sooner. For this portfolio, avalanche is modestly better mathematically. If the highest rate were 30%, savings would be larger. If all rates were similar (say 18% average and 19% max), the strategies would be nearly equivalent mathematically.

When Snowball Might Be Worth the Extra Cost

Behavioral research consistently shows snowball has higher completion rates than avalanche — people stick with snowball longer because early wins build momentum. A "worse" strategy you actually complete beats a "better" strategy you abandon. If you've tried avalanche previously and lost motivation, snowball's quick wins may be worth the extra 1,000-2,000 interest cost. Completion matters more than optimization for debt payoff.

What the Calculator Does Not Model

Specific debt ordering — calculator treats aggregate balance, which approximates but does not exactly model debt-by-debt payoff. Minimum payment requirements on each specific debt. Fees and promotional rate changes. Psychological factors that affect completion probability. Decisions about which specific debt to attack first within each strategy. The calculator shows approximate savings; exact math requires debt-by-debt amortization.