Carrying multiple debts is stressful, and knowing where to focus your extra payments can save you thousands. Two methods dominate the conversation: the debt snowball and the debt avalanche. Both work. The question is which one works best for your situation.
This guide walks through both methods clearly, uses a worked example with real numbers, and helps you decide which approach to take.
The Two Methods Explained
Debt Snowball
With the snowball method, you pay off your smallest balance first, regardless of interest rate. You make minimum payments on all other debts and throw every extra pound or dollar at the smallest one. When that debt is cleared, you redirect its payment to the next smallest, and so on.
The name comes from the idea that as you clear each debt, the amount you have available for the next one grows, like a snowball rolling downhill.
Debt Avalanche
With the avalanche method, you prioritise the debt with the highest interest rate first. Minimum payments go to everything else, and your extra money attacks the highest-rate debt. When that is cleared, you move to the next highest rate.
The name reflects the idea that high-interest debt is cascading against you. Stopping the avalanche first limits the damage.
A Worked Example
You have three debts:
| Debt | Balance | Interest Rate | Minimum Payment |
|---|---|---|---|
| Credit card A | 1,200 | 22% | 30/month |
| Personal loan | 4,500 | 11% | 95/month |
| Credit card B | 8,000 | 18% | 160/month |
You can afford 400 per month total, which gives you 115 extra after minimums (400 minus 285).
Using the snowball method:
You put the 115 extra towards credit card A (lowest balance). It clears in roughly 10 months. You then redirect that freed-up 145 (30 + 115) to the personal loan alongside the existing 95, making 240 per month on the loan. The loan clears in about 18 more months. You then attack credit card B with everything.
Total time: approximately 36 months. Total interest paid: roughly 2,800.
Using the avalanche method:
You put the 115 extra towards credit card A because it has the highest rate (22%). It still clears in about 10 months since the balance is small. You then redirect to credit card B (18%), the next highest rate. With 275 per month (160 + 115), credit card B takes roughly 28 more months. The loan runs in parallel.
Total time: approximately 36 months. Total interest paid: roughly 2,300.
The avalanche saves around 500 in this scenario. The timeline is similar because the highest-rate debt also happened to be one of the smaller balances. In cases where the highest-rate debt carries the largest balance, the savings can be significantly larger.
Use the Debt Payoff Calculator to model your own debts and see exactly what each method costs you.
When the Snowball Wins Psychologically
The avalanche is mathematically superior. But mathematics does not account for motivation.
The snowball creates quick wins. Clearing a debt completely, even a small one, gives you a sense of momentum that many people find genuinely motivating. If you have struggled to stick to debt repayment plans in the past, that psychological boost can be the difference between staying on track and giving up.
Several studies suggest that for people with multiple debts, the speed of early victories matters more to long-term success than the mathematical efficiency of the strategy. If seeing a zero balance keeps you going, the snowball is probably the better choice for you, even if it costs a bit more.
When the Avalanche Wins Mathematically
If you are disciplined, motivated by numbers, and comfortable tracking a longer-term plan without immediate visible progress, the avalanche will save you the most money. The higher your interest rates, the bigger the difference in outcome.
For people with high-rate credit card debt alongside lower-rate loans, the avalanche can save thousands compared to the snowball. This gap widens further if the repayment period is long.
The Hybrid Approach
Many people use a combination. They start with the snowball to clear one or two small nuisance debts quickly, which simplifies their financial picture and boosts confidence, then switch to the avalanche to optimise the rest.
This is entirely valid. The goal is to pay off all your debts, and any consistent strategy beats stopping and starting.
How Extra Payments Change Everything
One thing both methods share: extra payments have a disproportionate impact. Even small amounts applied consistently can dramatically shorten your repayment timeline.
In the example above, adding just 50 more per month to the snowball plan reduces total interest paid by around 300 and cuts several months off the timeline. The reason is compound interest: reducing principal early means you accrue less interest in future months.
If you come into any windfall, a tax refund, a bonus, or a freelance payment, applying it directly to your current target debt accelerates progress far more than it might seem.
You can also pair your debt strategy with a Loan Repayment Calculator to model specific loans and see how overpayments affect your schedule.
Choosing Your Strategy
Ask yourself two questions:
- Do I need quick wins to stay motivated, or can I stay the course without them?
- How much are my higher-rate debts costing me monthly?
If motivation is your biggest challenge: start with the snowball. If your high-rate debts are costing you a significant amount in monthly interest: use the avalanche.
Either way, the most important thing is to start. Both strategies require you to make minimum payments on everything and apply extra money consistently. The decision between snowball and avalanche is secondary to simply committing to a plan and sticking with it.