After-tax cost of debt is the net cost a company incurs on its debt after accounting for tax deductions. It is an important measure as interest expenses are tax-deductible, reducing the overall expense of borrowing.
Weighted Average Cost of Capital (WACC): A company's overall cost of capital from all sources, including equity and debt.
Tax Shield: The reduction in income taxes that results from taking an allowable deduction from taxable income.
Cost of Equity: The return required by shareholders for investing in a company's equity.