Capital Structure
Capital structure describes the mix of debt, equity, and hybrid instruments a company uses to finance its assets and ongoing operations, determining both the cost of capital and the distribution of financial risk between creditors and shareholders.
Every corporation must decide how to fund itself. Ford Motor Company, for example, carries enormous amounts of long-term bonds to finance its manufacturing plants and auto-loan portfolio, while a high-growth software company like Salesforce has historically relied more heavily on equity because its intangible assets offer little collateral for lenders. The resulting blend of financing sources is the firm's capital structure.
Capital structure appears on the right-hand side of the balance sheet. Long-term debt — including senior secured loans, unsecured bonds, and convertible notes — represents money owed to creditors with contractual interest and principal repayment obligations. Common equity represents the residual claim of shareholders. Preferred stock sits between the two: it has a fixed dividend (like debt) but no maturity date and ranks above common equity in liquidation (like a senior class of equity).
The optimal capital structure balances competing forces. Debt is cheaper than equity on a pre-tax basis because interest is tax-deductible and creditors demand lower returns given their senior claim. However, too much debt increases financial distress risk — if cash flows fall short of interest obligations, the company may default, as occurred with Toys 'R' Us in 2017 after its leveraged buyout burdened it with over six billion dollars in debt. Equity is more expensive but carries no fixed obligation.
Analysts measure a company's capital structure using ratios such as the debt-to-equity ratio (total debt divided by total equity), the debt-to-EBITDA ratio (a proxy for how many years of operating cash flow would be needed to retire debt), and the interest coverage ratio (EBIT divided by interest expense). Investment-grade US companies typically target debt-to-EBITDA below 3x, while high-yield issuers routinely operate above 5x.
Capital structure decisions affect shareholder returns through financial leverage. When a company earns returns on invested capital above its cost of debt, levering up amplifies equity returns — a concept called positive financial leverage. However, leverage is a double-edged effect: when returns fall below the cost of debt, shareholders absorb magnified losses. Understanding a company's capital structure is therefore essential before drawing conclusions about earnings quality, dividend sustainability, or valuation multiples.