The cost of capital is the return a company must earn on its investments to satisfy the providers of its capital. In practical terms, it is the price of financing.
If a business raises money from shareholders and lenders, those investors expect compensation for time, risk, and opportunity cost. The cost of capital is the rate that captures that expectation.
Why It Matters
Cost of capital is one of the most important concepts in corporate finance because it drives:
- project approval
- valuation
- capital budgeting
- financing decisions
If a company invests in projects that earn less than its cost of capital, it may be growing in size while destroying value.
The Big Picture
Most firms are financed with some combination of:
Each source has its own required return:
When these are combined according to the firm’s capital structure, the result is usually Weighted Average Cost of Capital (WACC).
Why Investors Require It
Providers of capital could always use their money somewhere else. So any company that wants access to funding must offer a return high enough to compete with those alternatives.
That required return depends on:
- business risk
- leverage
- interest rates
- market conditions
- the stability of cash flows
Safer and more predictable businesses usually face a lower cost of capital than highly uncertain businesses.
Cost of Capital in Valuation
When analysts value a company using Discounted Cash Flow (DCF), the cost of capital often becomes the discount rate used to convert future cash flows into present value.
This is why a small change in cost of capital can have a large impact on valuation:
- a higher cost of capital lowers present value
- a lower cost of capital raises present value
Cost of Capital in Capital Budgeting
Companies also use cost of capital as a benchmark for investment decisions.
If a project is expected to earn:
- more than the cost of capital, it may create value
- less than the cost of capital, it may destroy value
This is why cost of capital often serves as a decision threshold alongside metrics such as Net Present Value (NPV) and Internal Rate of Return (IRR).
FAQs
Is cost of capital the same as interest rate?
No. Interest rate is only part of the picture. Cost of capital also includes the return required by equity holders.
Why does cost of capital differ across companies?
Because companies differ in leverage, stability, growth risk, cyclicality, and market perception.
Can lowering cost of capital increase firm value?
Yes. A lower cost of capital raises the present value of future cash flows, all else equal.
In this section
-
Cost of Debt: The Effective Borrowing Rate a Company Pays to Lenders
Understand cost of debt, how it is estimated, and why the after-tax cost matters in WACC and valuation.
-
Cost of Equity: The Return Shareholders Require for Owning a Risky Business
Learn what cost of equity means, how CAPM estimates it, and why it matters in valuation and WACC.
-
Incremental Cost of Capital: Understanding the Cost of Raising Additional Finance
An in-depth exploration of the incremental cost of capital, its calculation, and its significance in financial decision-making.
-
Marginal Cost of Capital: Understanding the Cost of Additional Financing
An in-depth examination of the Marginal Cost of Capital, its importance in financing decisions, comparisons with average cost of capital, and its application in discounting cash flows.
-
Risk-Adjusted Discount Rate: Why Riskier Cash Flows Need a Higher Hurdle
Learn what a risk-adjusted discount rate is, how it is built, and why analysts use it to value riskier projects and cash flows.
-
WACC: Weighted Average Cost of Capital
An in-depth look into the concept of Weighted Average Cost of Capital, its calculation, significance, and applications.
-
Weighted Average Cost of Capital
Blended cost of debt and equity capital, used in valuation, project screening, and capital allocation.