The math says avalanche. The psychology says snowball. And honestly, the best method is whichever one you'll actually stick with for two to five years.
The debt avalanche method has you pay minimums on everything, then throw every extra dollar at the debt with the highest interest rate. Once that's paid off, you move to the next highest rate. This saves the most money in total interest. On $40,000 in mixed debt, the avalanche can save you $2,000 to $5,000 compared to the snowball, depending on your rate spread.
The debt snowball method (popularized by Dave Ramsey) has you pay off the smallest balance first regardless of interest rate. The idea is that quick wins build momentum. You see a $800 credit card disappear in two months, and that psychological boost carries you through the longer slog on the bigger balances.
Research from Harvard Business Review found that people who use the snowball method are more likely to eliminate their debt entirely. Not because the math is better (it isn't), but because motivation matters more than optimization when you're staring at a multi-year payoff timeline.
For 2026 specifically, interest rates on credit cards are averaging 22% to 28%. When your rates are clustered that closely together, the mathematical advantage of the avalanche shrinks. If your highest-rate card is at 27% and your lowest is at 22%, the interest savings from strict avalanche ordering are modest. In that environment, the snowball's motivational benefit might actually produce better real-world results.
There's also a hybrid approach worth considering: pay off one small balance first for the quick win, then switch to avalanche order for the rest. You get the psychological boost upfront and the math optimization for the bulk of the payoff.
If you're disciplined and motivated by numbers, use the avalanche. If you need visible progress to stay on track, use the snowball. If you're not sure, start with the snowball. You can always switch later.