Direct Answer
Interest expense is the cost a company incurs from interest owed on its outstanding debt. It's reported as a non-operating expense on the income statement, below operating income, and is subtracted, along with any interest income, to arrive at pretax income. Because higher debt levels and higher interest rates both push interest expense up, it's commonly examined alongside a company's leverage ratios.
Key Takeaways
- Interest expense reflects what a company pays to service its outstanding debt, not its cost of doing business.
- It sits below operating income on the income statement, in the non-operating section.
- It's subtracted, along with any interest income, to arrive at pretax income.
- Both rising debt balances and rising interest rates increase interest expense.
- Analysts commonly pair interest expense with leverage ratios to gauge debt-servicing burden.
What Is Interest Expense?
Interest expense is the cost a company incurs from interest owed on its outstanding debt, the loans, bonds, notes payable, and other borrowings it carries on its balance sheet. It's a financing cost, not an operating one: it arises from how a company chooses to fund itself (how much it borrows, and at what rate) rather than from running its core business.
That distinction is why interest expense is kept separate from operating expenses like cost of goods sold, salaries, or marketing. Two companies with identical operating performance can post very different bottom lines once financing costs are added in, simply because one carries more debt or borrowed at a higher rate.
Where Interest Expense Sits on the Income Statement
Interest expense is reported as a non-operating expense, below operating income. A simplified income statement typically flows in this order:
| Line item | Section |
|---|---|
| Revenue | Operating |
| Cost of goods sold, operating expenses | Operating |
| Operating income | Subtotal |
| Interest income | Non-operating |
| Interest expense | Non-operating |
| Pretax income | Subtotal |
| Income tax expense | Below the line |
| Net income | Bottom line |
In other words, operating income is calculated first, without regard to how the company is financed. Interest income and interest expense are then netted in below that line, and the result is pretax income, the income base to which tax expense is applied to arrive at net income.
Worked Example: From Operating Income to Pretax Income
Hypothetical example, for education only.
Suppose a company reports the following for a fiscal year:
| Line item | Amount |
|---|---|
| Operating income | $50,000,000 |
| Interest income | $1,000,000 |
| Interest expense | $(6,000,000) |
| Pretax income | $45,000,000 |
Here, operating income of $50,000,000 is adjusted for non-operating items: interest income of $1,000,000 is added, and interest expense of $6,000,000 is subtracted. Net, that's a $5,000,000 reduction ($6,000,000 − $1,000,000), bringing pretax income to $45,000,000 ($50,000,000 + $1,000,000 − $6,000,000). From there, income tax expense would be applied to reach net income.
Why Interest Expense Matters
Interest expense is one of the clearest signals of how much a company's capital structure is costing it. Because higher debt levels and higher interest rates both increase interest expense, a rising trend in this line item can reflect either the company taking on more debt, its existing debt repricing at higher rates, or some combination of the two.
That's why interest expense is commonly examined alongside leverage ratios, such as debt-to-equity or debt-to-EBITDA, and coverage ratios that compare operating income to interest expense. Viewed together, these metrics can help indicate how much cushion a company has between its operating earnings and the financing costs it's obligated to pay, though the appropriate level varies by industry, business model, and stage of growth, so context matters more than any single figure in isolation.
Limitations and Common Mistakes
- Treating it as an operating cost. Interest expense is a financing cost, not an operating one, mixing it into operating-expense analysis can distort operating margins.
- Ignoring interest income. Some companies report interest expense and interest income as separate lines, others net them together; check which convention a given company uses before comparing across filings.
- Assuming a fixed rate. Interest expense can shift with variable-rate debt, refinancing, or new borrowing, so it doesn't necessarily move in a straight line with total debt outstanding.
- Comparing across industries without context. Capital-intensive businesses typically carry more debt than asset-light ones, so an interest-expense comparison is generally more meaningful within an industry or against leverage ratios than in isolation.
Frequently Asked Questions
Is interest expense an operating expense?
No. Interest expense is reported as a non-operating expense on the income statement, below operating income, because it relates to how a company is financed rather than its core business operations.
How is interest expense calculated?
Interest expense reflects the interest owed on a company's outstanding debt over the reporting period, based on the balances and rates of its loans, bonds, and other borrowings. Along with any interest income. It is subtracted from operating income to arrive at pretax income.
Where does interest expense appear on the income statement?
Interest expense sits below operating income, typically in a non-operating section alongside interest income and other non-operating items, before the line for pretax income (also called income before taxes).
Why do analysts look at interest expense alongside leverage ratios?
Because both higher debt levels and higher interest rates increase interest expense, analysts commonly examine it together with leverage ratios to gauge how much of a company's earnings are being consumed by debt financing costs.
What is the difference between interest expense and interest income?
Interest expense is the cost a company pays on money it has borrowed, while interest income is money a company earns on cash, investments, or receivables. Both are typically netted together in the non-operating section before pretax income.
Why does reported interest expense differ from the coupon on outstanding debt?
The reported figure includes amortisation of issuance costs and any discount or premium, is net of any capitalised interest, and reflects the timing of borrowings during the period rather than the year-end balance. The effective rate therefore differs from the stated coupons. Dividing interest expense by average debt gives an effective rate that captures these effects.
What is capitalised interest and how does it affect the reported figure?
Interest incurred during construction of a qualifying long-lived asset is added to the asset's cost rather than expensed, which reduces reported interest expense during a construction period and increases future depreciation. Companies disclose the capitalised amount. A company in a large build phase therefore reports lower interest expense than it actually incurs.
How should interest income be treated alongside interest expense?
Some companies present a net figure and others present the two separately, which affects comparability. A company with substantial cash earning interest can report a small net expense while carrying meaningful debt. Separating the two is necessary before computing a coverage ratio, since netting understates the servicing burden.
How does interest expense respond to a change in market rates?
Floating-rate debt reprices with the benchmark so the effect appears quickly, while fixed-rate debt is unaffected until it matures and is refinanced. A company with mostly fixed debt therefore shows a delayed response concentrated at maturity dates. Combining the fixed and floating mix with the maturity schedule indicates when the effect will arrive.