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The Debt Snowball Method: Step-by-Step Guide for UK Borrowers

Published 21 March 2026 · About 6 min read

The debt snowball is a debt repayment strategy built around motivation. You pay off your debts in order of smallest balance to largest — not highest interest rate. Clearing accounts quickly gives you early wins that can keep you going. It isn't the cheapest method mathematically, but for people who've struggled to stick with a plan before, it can be the one that actually works.

How the debt snowball method works

The logic is psychological rather than mathematical. Each time you clear a debt entirely — even a small one — you close an account, reduce your number of monthly obligations, and prove to yourself that the plan is working. Research suggests that early wins in debt repayment significantly improve follow-through rates, which matters more than the theoretically optimal strategy if that strategy gets abandoned halfway.

The "snowball" name comes from the rolling motion: the payment from each cleared debt is added to the next, so the amount you're throwing at your target grows steadily as debts fall away.

Five steps to set it up

1

List all your debts with their balances

Write down every credit card, store card, overdraft, and personal loan — the balance, the APR, and the minimum payment for each. For this method, it's the balance column that determines your order, not the APR. You still need the APR to understand what you're paying, but it doesn't decide the attack sequence.

2

Sort by balance, smallest first

Rank your debts from the smallest balance to the largest. This is your snowball order. The smallest debt gets attacked first — everything else just gets the minimum for now.

3

Set up minimum payments on all debts

Use direct debits so you never miss a minimum. Even while focusing your extra payment on one target, every other debt must be kept current — late fees and credit file marks cost more than the marginal interest saving.

4

Put every extra pound at the smallest balance

Work out how much you can realistically pay each month above the sum of all your minimums. Put every penny of that extra at your smallest-balance debt. The goal is to clear it as fast as possible so you can cross it off and roll the payment forward.

5

Roll the payment when a debt clears

When your smallest debt hits zero, don't reduce your total monthly outgoing. Move the full payment — minimum plus extra — onto the next smallest balance. Your monthly commitment stays the same, but now it's all concentrated on one target instead of spread across two.

Worked example: three UK debts

The same three debts as the avalanche guide — same balances, same APRs, same £50 extra per month — but now sorted by balance:

DebtBalanceAPRMin paymentSnowball order
Store card£80034.9%£25① Attack first
Credit card£2,40022.9%£55② Next
Personal loan£4,5009.9%£110③ Last

In this example, the snowball and avalanche happen to produce the same sequence — the store card is both the smallest balance and the highest APR. This is relatively common and means the two methods give nearly identical results here. The gap between them opens up when the smallest balance is not the highest-rate debt — for instance, if the personal loan were £900 instead, the snowball would attack that first while the 34.9% store card kept accumulating interest.

Store card £800 cleared ~month 11 Credit card £2,400 cleared ~month 29 Personal loan £4,500 cleared ~month 47 Early wins build momentum Each cleared account rolls its payment into the next
Snowball order: smallest balance first. Each cleared debt adds its payment to the next target — the snowball grows as it rolls.

Snowball vs avalanche: the honest comparison

The snowball's main cost is interest. When your smallest balance happens to have a lower APR than a larger balance, you're paying minimums on the expensive debt for longer while you work through the small one. That extra interest compounds every month.

Snowball

Smallest balance first. Early account closures. Strong motivation. Usually costs more in total interest.

Avalanche

Highest APR first. Minimises total interest. Mathematically optimal. Takes longer to see first account cleared.

The key question is: how large is the gap in your case? Sometimes it's a few pounds; sometimes it's thousands. The only way to know is to run both scenarios with your real numbers. The free calculator shows your total interest and debt-free date for both methods side by side — in under a minute, no sign-up required.

Compare both methods with your own debts: Use the free calculator →

When the snowball is the right choice

When the avalanche is likely better

See the debt avalanche step-by-step guide for a full breakdown of the avalanche approach, and our main comparison article for a direct head-to-head.

Key takeaways

Try the free Debt Avalanche vs Snowball Calculator →