Cost of Equity

Cost of equity is the rate of return that shareholders require as compensation for the risk of owning a company's stock. It represents the opportunity cost of investing in that particular stock instead of a risk-free alternative like government bonds.

The most common method for estimating cost of equity is the Capital Asset Pricing Model, which adds a risk premium to the risk-free rate based on the stock's beta. The formula is: risk-free rate plus beta times the equity risk premium.

Role in Valuation

Cost of equity is a key input for calculating WACC, which serves as the discount rate in DCF analysis. A higher cost of equity increases the discount rate, which reduces the present value of future cash flows and lowers the calculated fair value. A lower cost of equity has the opposite effect.

Stable, established companies with predictable cash flows typically have lower costs of equity (8 to 10 percent) because investors perceive less risk. Volatile, unprofitable, or early-stage companies have higher costs of equity (12 to 18 percent or more) because the uncertainty demands greater compensation.

Cost of equity is always higher than cost of debt because equity holders bear more risk — they are last in line during bankruptcy and have no guaranteed returns. This is why increasing debt up to a point can lower a company's overall WACC.