Same money, two orders of attack
Both strategies follow the same rule: pay the minimum on everything, and throw every extra dollar at a single target debt until it dies — then roll its entire payment into the next target. The only difference is the order of targets. The snowball goes smallest balance first, trading a little interest for early victories. The avalanche goes highest rate first, which minimizes interest in this fixed-rate model when payments and fees are otherwise identical.
The right question isn’t “which is optimal?” — it’s “how much does optimal actually pay me?” If the avalanche saves $180 over three years, take whichever keeps you motivated. If it saves $3,000, that’s a real argument for gritting your teeth through the big ugly balance first. The calculator above answers it with your numbers.
Making either method work
- Automate the minimums so a missed payment never adds fees or penalty APRs to the plan.
- Fix the extra amount as a recurring transfer the day after payday — money that sits in checking gets spent.
- Roll over payments immediately. The power of both methods comes from the growing payment hitting each successive target.
- Stop adding debt. A card that keeps getting used is a bucket with a hole in it; freeze it until the plan is done.
Method, example, and sources
How this calculator works
The simulation accrues interest monthly, pays every listed minimum, and sends the remaining monthly budget to one target debt. Snowball sorts targets by smallest balance; avalanche sorts them by highest APR. When a balance reaches zero, its former minimum remains in the shared budget for the next target.
Worked example
The default example has $24,000 across three debts, $480 in combined minimums, and $300 extra each month. Keeping that same $780 monthly budget, the model estimates about 45 months and $10,975 of interest for snowball versus 41 months and $7,856 for avalanche — a modeled $3,118 difference before display rounding.
What the estimate leaves out
- APRs, minimum payments, and the monthly extra amount are assumed to stay unchanged.
- New purchases, late fees, promotional rates, balance-transfer fees, and payment-allocation rules are excluded.
- A hardship plan, consolidation offer, or negotiated rate change cannot be modeled by simply reordering the debts.
Primary sources
Frequently asked questions
What is the difference between the debt snowball and the debt avalanche?
Both methods pay minimums on every debt and direct all extra money at one target debt. The snowball targets the smallest balance first — quick wins for motivation. The avalanche targets the highest interest rate first — mathematically optimal. When a debt is paid off, its payment rolls into the next target.
Which method saves more money?
The avalanche always saves at least as much interest as the snowball, because it kills expensive debt first. But the gap is often smaller than people expect — run your own numbers above. If the difference is small, the strategy you actually stick with is the better one.
Why do so many people recommend the snowball if the avalanche is optimal?
The snowball produces earlier account closures, which some people find easier to sustain. That benefit is personal rather than guaranteed. The CFPB presents both methods: compare their cost here, then choose the order you can follow while keeping every required payment current.
Should I include my mortgage or student loans?
Include only debts you genuinely plan to attack with the same fixed monthly budget. A mortgage, secured debt, federal student loan with repayment protections, or debt on a forgiveness path may not be comparable to revolving consumer debt. Model those obligations separately before redirecting required payments.
What if I can’t pay more than the minimums?
Both methods can still work with $0 extra when every minimum covers that debt’s monthly interest: once one balance is cleared, its old minimum rolls into the next target. Extra money speeds up the plan, but it is not required for the rollover to work. If a minimum does not cover interest, ask the issuer or a nonprofit credit counselor about hardship options.