Debt has a bad reputation, and in many cases that reputation is deserved. High-interest consumer debt is a significant source of financial stress and can take years to escape. But the blanket idea that all debt is bad obscures a more useful distinction: some debt is a financial tool that enables wealth-building, and some debt is a drain that consumes future income for past consumption.
Understanding the difference is not about becoming comfortable with borrowing. It is about making informed decisions when debt is involved.
What makes debt good or bad
The core distinction is what the borrowed money is used for, and whether the asset or outcome it purchases is likely to be worth more — or produce more — than the cost of the debt.
Good debt, loosely defined, is debt taken on to acquire an asset that appreciates in value, generates income, or increases your earning capacity. The debt is doing productive work: it is financing something that grows or produces, and the expected return exceeds the interest cost.
Bad debt is debt used to finance consumption or the purchase of assets that depreciate. The interest paid is pure cost, the asset (if any) shrinks in value, and the net effect is a transfer of future income to pay for past experiences or goods.
The distinction is not always clean in practice, and the same type of debt can be good or bad depending on the specific terms and circumstances. But the framework is a useful starting point for any borrowing decision.
Examples of productive debt
A mortgage at a reasonable interest rate is the most commonly cited example of good debt. Property, over long time horizons, has generally appreciated in value in most markets, and the alternative to borrowing is renting — which is also a cost, without the asset accumulation. A mortgage at 4% on a property that appreciates at 3-5% per year, while providing housing, is debt that is doing useful work.
The “reasonable terms” qualifier matters enormously. A mortgage that commits you to repayments that are too high relative to your income, or at a variable rate that could rise sharply, or on a property in a market unlikely to appreciate, is a different proposition.
A student loan used to fund education that materially increases earning potential is another commonly cited example. If the additional lifetime income from the credential substantially exceeds the debt and interest cost, the economics are favourable. Not all degrees achieve this, and the calculation requires an honest assessment of the specific credential and career path.
Business debt used to fund operations or expansion that generate returns above the cost of borrowing is classic productive leverage — this is how most businesses work.
Examples of destructive debt
Car loans on new or nearly-new vehicles are perhaps the purest example of debt used to finance depreciation. A new car loses 15-25% of its value in the first year and continues to depreciate throughout its life. Borrowing to finance an asset that shrinks means paying interest on something worth progressively less. The total cost over the life of the loan — purchase price plus interest — is often significantly more than the car will ever be worth.
Credit card debt carried month-to-month is the most expensive form of consumer debt in most markets, with interest rates that typically range from 20-40%. Using a credit card for spending you cannot immediately repay is effectively borrowing at very high rates to fund current consumption. This is structurally guaranteed to make you poorer.
Personal loans for holidays, weddings, luxury goods or electronics are financing consumption and experiences. There is nothing inherently wrong with any of these things, but borrowing to pay for them means paying interest on top of the original cost, and the experience or item provides no return that offsets that cost.
The interest rate threshold
A useful rule of thumb: any debt above roughly 6-7% interest rate deserves urgent attention, because the guaranteed cost of that debt (the interest) almost certainly exceeds the expected return on any investment you could make with the same money.
Prioritising repayment of high-interest debt is therefore usually the highest-return financial move available to someone carrying it. Paying off 20% credit card debt produces a 20% guaranteed “return” — better than any realistic investment.
Debt below 4-5% (a typical mortgage rate in moderate-rate environments) is less urgent to repay aggressively, because the expected return on invested savings may exceed the cost of the debt.
Between those thresholds, the decision depends on your risk tolerance and personal comfort with debt.
Debt as a tool, not a lifestyle
The most important principle about debt is not that it is always bad or always acceptable — it is that it should be a deliberate, considered financial tool, not a default response to wanting something you cannot currently afford.
Before taking on any debt, the productive questions are: what is this financing? What will it be worth when the debt is paid off? What is the total cost including interest? And: is there a realistic plan to repay it?
Debt taken on without honest answers to these questions is almost always destructive, regardless of what category it theoretically falls into.
