Debt Snowball Calculator

This tool is for anyone juggling several debts — credit cards, store cards, a car loan, a personal loan — who feels like they're treading water. It applies the Debt Snowball method, a strategy built on behavioural momentum rather than pure maths: you clear the smallest balance first for a quick psychological win, then roll that freed-up payment into the next debt, and so on until you're debt-free.

If you owe money across multiple accounts and want a clear, motivating plan rather than a spreadsheet of minimum payments, this is the place to start.

• The current balance on each debt — not the original amount you borrowed.
• The interest rate (APR) on each, from your statement or online account.
• The minimum monthly payment each lender asks for.
• An honest figure for the extra you can throw at debt each month on top of all the minimums. Use our Budget Planner to find it — it's your income minus essential spending.

Keep a small starter emergency fund (around £1,000) before going all-in on debt; otherwise the next unexpected bill sends you straight back to the credit card.

• Debt Name — a label so you can tell your cards and loans apart (e.g. "Barclaycard", "Car Loan").
• Balance (£) — what you still owe today.
• Rate % — the annual interest rate. The snowball ignores this for ordering purposes, but it's useful context and matters if you're comparing against the avalanche method.
• Min Pay (£) — the minimum the lender requires each month. You keep paying this on every debt throughout the plan.
• Extra Monthly Payment (£) — the additional amount you direct at your smallest balance. This is the fuel for the snowball; the bigger it is, the faster you finish.

The snowball ignores interest rates when choosing what to attack first. Instead it ranks debts by balance, smallest to largest:

1. List every debt from smallest balance to largest, regardless of APR.
2. Pay the minimum on every debt except the smallest.
3. Throw your entire "extra" payment at the smallest balance until it's gone.
4. When it's cleared, take the money you were paying on it (minimum + extra) and add it to the next-smallest debt's minimum.
5. Repeat. Each cleared debt "snowballs" into the next, so your payment on the final debt is the sum of everything — powerful and motivating.

The summary panel shows your total debt, total minimums, and the combined monthly amount you'll commit throughout the plan.

Three debts and £150 extra each month:

• Store Card: £500 balance (Min pay: £25)
• Credit Card: £2,000 balance (Min pay: £60)
• Car Loan: £8,000 balance (Min pay: £200)

You pay minimums on the Credit Card and Car Loan, and attack the Store Card with its £25 minimum plus your £150 extra (£175 total). The Store Card clears in about 3 months. Now you roll that £175 onto the Credit Card's £60 minimum — £235 a month — and it disappears fast. Finally, the full £435 a month lands on the Car Loan. Each step is faster than the last because the payment keeps growing.

The snowball's rival is the avalanche, which targets the highest interest rate first. Mathematically the avalanche saves more money, because you kill the most expensive debt earliest. But research on real people shows the snowball has a higher completion rate, because the early "win" of clearing a whole account keeps motivation high. If you have a single debt at a punitive rate — a payday loan, for example — clear that first regardless of balance, then snowball the rest. For a deeper comparison, read our Snowball vs Avalanche guide.

• Taking on new debt mid-plan. The snowball only works if you stop digging. Cut up or freeze the cards while you execute it.
• Absorbing freed-up payments. When a debt clears, the temptation is to spend that minimum on lifestyle. You must roll it into the next debt or the maths collapses.
• Skipping the emergency fund. Without a small cash buffer, every surprise expense becomes new debt and resets your progress.
• Ignoring a predatory rate. The snowball orders by balance, but a payday loan at four-figure APR should be cleared immediately regardless of size.

• Use the Budget Planner to maximise your "extra" payment — even an extra £50 a month shaves months off the plan.
• Once debt-free, redirect the entire snowball payment into savings so the habit isn't lost — your first goal should be a full 3–6 month emergency fund.
• If you're struggling to meet minimums, contact a free debt charity such as StepChange before things escalate.
• Check whether a 0% balance-transfer card could reduce interest while you snowball — but only if you won't be tempted to spend on it.

• Budget Planner: Find the extra cash to fuel your snowball.
• Savings Goal Calculator: Plan your emergency fund before tackling debt.
• Debt Snowball vs Avalanche Guide: The full comparison of the two methods.
• Escaping Credit Card Debt Guide: Balance transfers and breaking the debt spiral.

SmartMoneyTools checks statutory rates and thresholds against official government publications. Results are estimates for educational purposes and may not reflect every individual circumstance. Last reviewed: 11 September 2026.

The debt reduction strategies discussed align with guidance from major financial counselling organisations:

• StepChange Debt Charity — free independent debt advice
• MoneyHelper — dealing with debt
• Citizens Advice — managing creditors and debt solutions