Debt Snowball & Avalanche Calculator

Debt Payoff Strategy Guide

What's the difference between Snowball and Avalanche?

Debt snowball: pay minimums on all debts, put extra money toward the smallest balance first. When a debt is cleared, roll its payment to the next smallest. Creates 'quick wins' that build psychological momentum. Debt avalanche: pay minimums on all debts, put extra money toward the highest interest rate first. Mathematically optimal — saves the most interest. Research shows snowball is often more effective in practice because motivation matters — the quick wins from clearing smaller debts keep people motivated to continue, even though avalanche saves more in total interest over the full payoff period.

What should I know about The Snowball Effect?

The key to both strategies is rolling over the full payment when a debt is cleared. If you pay £70 minimum on a credit card and it gets paid off, add that £70 to the next debt's payment — do not spend it. This creates an accelerating debt paydown: each cleared debt adds to the monthly payment attacking the remaining debts. A £150 extra payment plus two cleared minimums of £70 and £160 becomes £380/month attacking the last debt.

When to Consolidate Instead?

If the highest-rate debt is much larger than the others, a debt consolidation loan at a lower rate may save more than either strategy. Compare: (a) total interest on your current plan, (b) total interest on a consolidation loan that combines all debts at a lower rate. Balance transfer cards (0% for 12–24 months) are highly effective for credit card debt — moving balances to 0% and paying aggressively during the promotional period eliminates interest entirely for that period.

What do I need to know about Staying Motivated?

Debt payoff typically takes years. Strategies that help: use a visual debt tracker (colouring in a thermometer as debt reduces). Celebrate milestones (first debt cleared, halfway, last £1,000). Automate the minimum payments — set up direct debits so minimums cannot be missed. Focus on the extra payment rather than the minimums. Track your net worth monthly — watching it improve while debt falls is motivating. Avoid adding new debt while paying off existing debt — cut up credit cards or freeze the ones you're paying off in a block of ice if temptation is a genuine risk — it sounds extreme, but it works for some people.