Paying down debt: avalanche and snowball
Most households carry more than one debt, each with its own balance, rate and minimum payment. The question is which to pay first. The avalanche aims extra money at the highest rate. The snowball aims it at the smallest balance. This lesson runs both on four invented debts, shows how much they differ and when they do not, and sets the household against New York Fed debt balances and Federal Reserve interest rates. A calculator moves the extra payment and the two middle rates.
- Level
- Beginner
- Reading time
- About 24 minutes
- Know this first
- Emergency funds and savings goals
By the end you will be able to:
- explain how the avalanche and snowball methods choose which debt to pay first
- say why a minimum payment alone leaves debt in place for years
- compare total interest and time to debt-free under each method
- see when the two methods give the same result
- read national debt balances and interest rates without taking them as advice
Which debt first?
A household with one debt knows what to do with spare money. A household with several has a choice, and the choice changes how much interest it pays and how soon it is free. Two methods have names. The avalanche puts every spare dollar on the debt with the highest interest rate. The snowball puts it on the debt with the smallest balance. In both, the other debts get only their minimum payment until their turn.
This lesson runs both on four invented debts, so every figure can be checked. It shows that the avalanche costs less interest, how large the difference is, and when there is no difference at all. It also sets the household against real figures from the Federal Reserve Bank of New York and the Federal Reserve.
Four debts
The household owes four amounts. Each has a balance, a yearly interest rate and a minimum payment, the smallest amount the lender requires each month. Interest is added each month at one twelfth of the yearly rate. Together the minimums are $440 a month, and the household keeps paying that total throughout. As each debt is cleared, its minimum is not spent elsewhere. It rolls onto the next debt in line, which is the part of both methods that makes them faster than paying minimums alone.
| Debt | Balance, $ | Rate a year | Minimum a month, $ |
|---|---|---|---|
| Store card | 800 | 27% | 30 |
| Credit card | 3,000 | 22% | 90 |
| Personal loan | 2,500 | 12% | 100 |
| Car loan | 9,000 | 7% | 220 |
| Total | 15,300 | 440 |
The two methods give two different orders for the extra money.
| Order of the extra money | First | Second | Third | Fourth |
|---|---|---|---|---|
| Avalanche, highest rate first | Store card, 27% | Credit card, 22% | Personal loan, 12% | Car loan, 7% |
| Snowball, smallest balance first | Store card, $800 | Personal loan, $2,500 | Credit card, $3,000 | Car loan, $9,000 |
The avalanche follows the rate. The snowball follows the balance, so it clears the store card, then the personal loan, then the credit card. The two orders differ only in the middle, where the credit card has the higher rate but the personal loan has the smaller balance. How the cards work is covered in the lesson on credit cards and revolving debt, and the yearly cost of a loan in the true cost of borrowing.
What households owe
The Federal Reserve Bank of New York reported total US household debt of $18.771 trillion in the second quarter of 2026. Mortgages were the largest part, and credit cards were $1.263 trillion.
| Type of debt, second quarter 2026 | Balance, $ trillions | Share of total |
|---|---|---|
| Mortgages | 13.117 | 69.9% |
| Auto loans | 1.713 | 9.1% |
| Student loans | 1.651 | 8.8% |
| Credit cards | 1.263 | 6.7% |
| All other debt (calculated) | 1.027 | 5.5% |
| Total household debt | 18.771 | 100.0% |
Mortgages were 69.9% of household debt and credit cards were 6.7%. The last category is calculated as the total less the four types named in the release, so it includes whatever else the source counts. Interest rates differ a great deal by type, and the Federal Reserve publishes them in its G.19 release.
| Loan type, second quarter 2026 | Interest rate a year |
|---|---|
| Credit card plans, accounts assessed interest | 22.15% |
| Credit card plans, all accounts | 20.94% |
| Personal loans, 24-month | 11.86% |
| New car loans, 60-month | 7.14% |
| New car loans, 72-month | 6.97% |
In the second quarter of 2026 the average rate on credit card accounts assessed interest was 22.15%, compared with 11.86% on 24-month personal loans and 7.14% on 60-month new car loans. The invented household’s rates of 22%, 12% and 7% are chosen to match these three, which is why the credit card, the personal loan and the car loan are the ones in the lab. The G.19 figures are averages for the whole country, and individual rates vary with the borrower and the lender. The store card rate of 27% is invented and is not from the release.
Run both methods
Set how much extra the household pays each month on top of the $440 of minimums, and the rates on the credit card and the personal loan. The calculator runs each method month by month until all four debts are cleared. It reports the month the first debt is gone, the months to be debt-free, the total interest, and how much interest is saved compared with paying only each debt’s minimum with no rolling. The starting settings are $300 extra, a card at 22% and a loan at 12%.
Paying $300 a month on top of $440 of minimums, the avalanche clears all four debts in 23 months with $1,475 of interest, and the snowball in 23 months with $1,586. The avalanche costs $111 less interest and finishes in the same number of months. Paying only the minimums on each debt would take 52 months and cost $3,818 in interest.
Four experiments. First, leave the starting settings alone. The avalanche clears everything in 23 months with $1,475 of interest, and the snowball takes the same 23 months with $1,586. The avalanche saves $111, and both save a great deal against minimum payments alone, which would take 52 months and cost $3,818 in interest. Second, set the extra payment to nothing. The two methods now give the same result, 43 months and $3,563, but rolling the freed minimums still saves $255 against paying each minimum on its own. Third, set the credit card to 12% and the personal loan to 22%. Now the highest rate and the smallest balance point to the same debts in the same order, so the methods are identical and each pays $1,422 in interest. Fourth, set the extra payment to $800, the card to 30% and the loan to 5%. The avalanche attacks the 30% card and finishes in 13 months with $787 of interest. The snowball goes for the small store card first and takes 14 months and $967, so the avalanche saves $180. The snowball does clear its first debt sooner, in month 1 against month 4, which is the appeal some people find in it.
What the results mean
Three points come out of the experiments. First, the biggest saving is not from choosing the better method but from paying more than the minimums, and from rolling each freed minimum onto the next debt. Second, the avalanche never paid more interest than the snowball in these runs, but the gap was modest, tens or low hundreds of dollars on $15,300 of debt. Third, the two methods can coincide, as in the third experiment, so before choosing it is worth checking whether they differ at all.
The snowball clears debts sooner, and some people find that motivating. Whether that helps a person keep going is a question about behaviour that the numbers here cannot answer. The lesson on behavioural biases covers how people make decisions that are not purely arithmetic. A third route is to lower the rate itself, which is the subject of refinancing and restructuring.
What this lesson leaves out
- Four invented debts. The balances, the minimums and the store card rate are made up. The credit card, personal loan and car loan rates are chosen to be close to the national averages quoted.
- Fixed minimums. Real cards often set the minimum as a share of the balance, so it falls as the balance falls. Here each minimum is a fixed dollar amount.
- One constant payment. The household pays the same total every month. Real budgets change, and a missed payment would add fees.
- No fees, penalties or new borrowing. Late fees, promotional rates and further charges on the cards are left out.
- Interest on interest by month. Interest is added monthly at one twelfth of the yearly rate and rounded to the cent. Lenders’ own methods differ in detail.
- National averages. The New York Fed and Federal Reserve figures describe all US households and lenders, not this one.
- No advice. The lesson compares two methods. It does not tell any person which debt to pay.
Common mistakes
Paying only the minimums
A minimum is the smallest amount the lender requires, not a plan to clear the debt. In the model they take 52 months and cost $3,818 in interest.
Not rolling the freed payment
When a debt is cleared, its minimum should move to the next debt. Otherwise the speed-up is lost.
Choosing a method without comparing rates
If the highest rate and the smallest balance are on the same debt, the two methods are the same.
Ignoring the rate on the biggest debt
A low rate on a large balance, like the car loan here, can still cost real money, but a high rate costs more for each dollar owed.
Taking on new debt while paying down old debt
New charges on a cleared card restart the problem. The model assumes no new borrowing.
Try it yourself
1. A balance of $3,000 is charged 22% a year. About how much interest is added in the first month?
Show the working
22% ÷ 12 = 1.8333% a month, and 3,000 × 0.018333 = $55.
2. The four minimums are $30, $90, $100 and $220. What is the total, and what is the total with $300 extra?
Show the working
30 + 90 + 100 + 220 = $440. With the extra, 440 + 300 = $740 a month.
3. Which debt does the avalanche target first at the starting settings, and which does the snowball?
Show the working
Both start with the store card, the highest rate at 27% and the smallest balance at $800. They differ next: the avalanche goes to the 22% credit card and the snowball to the $2,500 personal loan.
4. At the starting settings the avalanche pays $1,475 in interest and the snowball $1,586. What is the difference?
Show the working
1,586 − 1,475 gives $111 less under the avalanche, from the same payments each month.
5. With the credit card at 12% and the personal loan at 22%, which method is cheaper?
Show the working
Neither. The highest-rate order and the smallest-balance order are then the same, so both pay $1,422 in interest.
Where this is used
- A household with several cards and loans chooses an order for extra payments.
- A credit counsellor or planner compares the total interest of different repayment plans.
- A lender or regulator reads household debt balances to judge how much stress there is on borrowers.
- A business with several loans decides which to repay early, using the same logic of rates against balances.
- An analyst compares interest rates across loan types, as the Federal Reserve’s G.19 release does.
Key terms
- Debt avalanche
- Paying extra on the debt with the highest interest rate first.
- Debt snowball
- Paying extra on the debt with the smallest balance first.
- Minimum payment
- The smallest payment a lender requires each month.
- Rolling payments
- Moving a cleared debt’s payment onto the next debt.
- Interest rate
- The yearly cost of borrowing, as a share of the balance.
- Balance
- The amount still owed.
- Debt-free date
- The month when every balance reaches zero.
- Revolving debt
- Borrowing, such as a card balance, that can be repaid and borrowed again.
Questions people ask
Which method is better?
The avalanche costs less interest, or the same when the orders coincide. The snowball clears the first debt sooner. The numbers show the cost of each choice. They do not say which suits a particular person.
Why does paying only the minimum take so long?
Because interest takes a share of every payment, so the balance falls slowly. In the model the minimums alone take 52 months.
Should an emergency fund come before paying down debt?
The previous lesson showed that a shock larger than the fund has to be borrowed. This lesson does not rank the two, because the answer depends on the rates and the household.
What if I can lower the rate instead?
A lower rate reduces interest directly. The lesson on refinancing explains how to test whether it pays.
Sources and review
- Federal Reserve Bank of New York, Household Debt and Credit Report, second quarter 2026 (press release, 11 August 2026), for total household debt and the mortgage, auto loan, credit card and student loan balances.
- Board of Governors of the Federal Reserve System, Consumer Credit (G.19) (release of 7 August 2026), for the interest rates on credit card plans, 24-month personal loans and new car loans in the second quarter of 2026 (preliminary, not seasonally adjusted).
How the numbers were checked: the month-by-month repayment of the four debts was recomputed in plain code in whole cents for both methods and for the minimums-only case, and the four experiments were read from that code. The shares of household debt were recalculated from the balances. The calculator, which runs separately, was compared with that code for every combination of settings it allows. The debts are invented.