Paying Off Debt Strategically

Avalanche: pay the minimum on every debt, then send every extra dollar to whichever balance carries the highest interest rate. Once that one's gone, roll its entire payment into the next-highest rate, and so on. This minimises total interest paid, mathematically, every time — the highest rate is where each extra dollar prevents the most future interest.

The logic doesn't depend on the size of any particular balance. A $1,200 card at 19% APR and a $5,000 loan at 12% APR both accrue interest every single month regardless of how you feel about them; avalanche just always points the spare dollar at whichever one is currently the most expensive to be carrying.

Snowball: pay the minimum on every debt, then send every extra dollar to whichever balance is smallest, regardless of rate. It usually costs somewhat more in total interest, but it clears an entire debt off the list fastest — a visible finish line early on, which is what keeps a lot of people actually sticking with the plan for the debts still ahead.

That's not a hand-wave. Behavioural research on debt payoff consistently finds that closing an account entirely — not just shrinking it — is what people report as motivating, in a way that a slightly smaller balance on three still-open accounts isn't. Snowball is a plan built around that fact, deliberately, rather than around the spreadsheet math avalanche optimises for.

The chart above runs both methods on the same three debts — two cards and a personal loan, $9,200 total — against the same $400 monthly budget. Here are the actual numbers behind it, not just the shape of the lines.

Snowball costs about $73 more in total interest over the entire payoff — a small amount, spread across more than two years — in exchange for closing an entire account eight months sooner. Both plans reach zero in the same 28th month here, which is notable: the total time to debt-free doesn't always diverge as much as people assume. What actually differs between the two methods is the interest total and which debt disappears first, not necessarily how long the whole thing takes.

Avalanche and snowball both assume the debts themselves stay fixed and only the payment order changes. Two other moves change the debts instead — and both can help or backfire, depending on the fine print.

Refinancing replaces an existing loan with a new one, usually to get a lower rate. It goes wrong in a specific way: refinancing resets the clock. A car loan three years into a five-year term has already paid down most of its early, interest-heavy months; refinancing into a fresh five-year term at a lower rate can still mean paying more total interest, because you've restarted the part of the schedule where payments are mostly interest. On federal student loans specifically, refinancing into a private loan is a one-way door — it permanently forfeits income-driven repayment and forgiveness eligibility that the federal loan carried, in exchange for a rate that may only be marginally better.

Consolidation combines several debts — usually credit cards — into one loan or one balance-transfer card. The failure mode here is behavioural rather than mathematical: the old cards get paid to zero but stay open, and it is very easy to run them back up while also paying down the new consolidation loan, ending up with more total debt than before. A 0% balance-transfer offer adds a second trap — a 3% transfer fee upfront ($150 on a $5,000 balance) is real interest even during the “0%” window, and whatever balance is left when the 18-month promotional period ends reverts to a standard APR, often above 20%.

1. 1
   Compare the new rate to your current weighted-average rate, after fees.

   An origination fee or transfer fee can erase a rate cut that looks good on paper.

2. 2
   Check whether the term resets.

   A lower monthly payment on a longer term can mean more total interest, not less.

3. 3
   If it's a federal student loan, confirm what protections you'd be giving up.

   Income-driven repayment and forgiveness eligibility don't come back once you refinance to private.

4. 4
   Decide what happens to the old accounts before you consolidate.

   A paid-off card that stays open and unused is fine. A paid-off card you keep spending on is a second debt stacked on the first.