Weighted Average Cost of Capital (WACC)
Definition
The Weighted Average Cost of Capital (WACC) is the blended rate of return that a business must generate to satisfy both its debt holders and its equity holders. It represents the minimum return the business needs to produce to justify the capital invested in it.
WACC combines two components, weighted by how much of each makes up the company’s capital structure:
- Cost of Debt — what lenders charge (interest rate, adjusted for the tax deduction on interest)
- Cost of Equity — what equity investors require as a return for the risk they’re taking
The Formula
WACC = (After-Tax Cost of Debt × Debt Weight) + (Cost of Equity × Equity Weight)
Example using Advanced Solutions 1.0:
- After-tax cost of debt: 7.5% (10% interest × 75% after tax shield)
- Debt weight: 35%
- Cost of equity: 30%
- Equity weight: 65%
- WACC = (7.5% × 35%) + (30% × 65%) = 2.6% + 19.5% = 22.1%
Why WACC Matters for Owners
WACC is the denominator in the valuation equation. The multiple a buyer applies to your business is essentially 1 ÷ WACC. A WACC of 22.1% produces a 4.52× multiple. A WACC of 18.9% produces a 5.3× multiple. That difference — driven entirely by risk reduction — is worth over 1.5M of EBITDA.
This is why risk, not revenue, drives business value. Every module in the iBD Ownership OS™ ultimately works to reduce the company-specific risk component of the owner’s cost of equity — which flows through WACC into the multiple and into enterprise value.
Where This Concept Appears
- Lesson 36 — Full teaching lesson on WACC and the multiple
- Case Studies — Advanced Solutions 1.0 (22.1% WACC, 4.52×), Rockin’ Times (18.9% WACC, 5.3×), Advanced Solutions 2.0 (15% WACC, 6.67×)
- Module 2 (Expand Knowledge) — Core to Lens 2: Market Value