This is one of the most common questions in personal finance, and the honest answer is that it depends. The mathematically optimal choice is usually to pay off high-interest debt before building savings, because the interest rate on credit card debt is almost always higher than the return you will get from a savings account. But the mathematically optimal choice is not always the best choice for an actual human being trying to manage their financial life sustainably.
The case for paying off high-interest debt first
Credit card interest rates are typically 18 to 28 percent or higher. A high-yield savings account earns around 4 to 5 percent. Every dollar sitting in a savings account while you carry a credit card balance is effectively losing 13 to 23 percent per year. The guaranteed return on paying down debt is the interest rate you stop paying, which easily outperforms any savings product. If you have high-interest debt and can only do one thing, the math strongly favors attacking the debt.
The case for building a small savings buffer first
The behavioral counterargument is that most people who have high-interest debt also have no savings cushion, and that combination is a trap. Every unexpected expense, a car repair, a medical bill, a sudden income gap, goes right back onto the credit card, undoing weeks of debt payoff progress. A small savings buffer of $500 to $1,000 breaks that cycle. Even though saving first is not mathematically optimal, it creates the stability that makes sustained debt payoff actually possible.
One important exception: employer match on your 401(k)
If your employer matches retirement contributions and you are not contributing enough to get the full match, that match is effectively a 50 to 100 percent instant return on your money. No debt payoff can beat that. Most financial advisors recommend contributing at least enough to capture the full employer match before directing extra money to debt payoff, even high-interest debt.
For most people, a split approach works best
A practical approach for most households: build a small emergency buffer to $500 or $1,000, contribute enough to capture any employer retirement match, and then put as much extra as possible toward the highest-interest debt. Once high-interest debt is paid off, redirect those payments to the next priority, whether that is building a fuller emergency fund, paying off lower-interest debt, or increasing retirement savings. This is not the mathematically perfect sequence, but it is realistic and sustainable.
Low-interest debt changes the equation
Debt at 4 to 6 percent, such as many mortgages or subsidized student loans, is a different calculation than credit card debt at 24 percent. When the interest rate on debt is close to or below what you could reasonably earn by saving or investing, paying it down aggressively becomes much less compelling. Many people with low-interest debt are better served by making minimum payments and directing extra cash toward savings or investments that are likely to outperform the interest cost over time.