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CFA Level I · CFA Level I Exam

Capital Structure for CFA Level I: Chapter Guide

Capital structure is the mix of debt and equity a firm uses to fund its assets. For CFA Level I, you learn how that mix changes WACC and firm value under Modigliani-Miller, distress costs, trade-off theory, pecking order and signaling, then how analysts set a target structure.

What this chapter covers

Capital structure asks one question: how should a company split its funding between debt and equity? The chapter starts with the basic link between financing mix and the weighted average cost of capital (WACC). It then builds theory in layers. Modigliani-Miller gives the clean starting point with no taxes. Taxes, financial distress costs and agency costs make the picture more realistic. Pecking order and signaling explain how managers actually behave.

You will work with a few formulas and many cause-and-effect statements. The formulas are short, such as WACC = (E ÷ V) × rE + (D ÷ V) × rD × (1 − t), and the M&M Proposition II relationships. Most questions test whether you know which way a variable moves when leverage rises, and under which assumptions.

This chapter sits inside Corporate Finance, and it connects to several other topics. WACC is used in discounted cash flow valuation in Equities. Leverage ties to risk and ratio analysis in Financial Statement Analysis. The cost of equity links to CAPM ideas from Portfolio Construction. Debt cost and credit risk link to Fixed Income. Learn this chapter well and those other areas become easier.

Corporate Finance carries a moderate topic weight (6-9%), and Capital Structure is a concept-heavy part of it. The questions are standalone three-option MCQs, so a few clear rules let you eliminate two options fast. The direction-of-change logic (does WACC rise or fall, does cost of equity rise or fall) also supports valuation questions elsewhere. Because there is no penalty for wrong answers and no minimum score per topic, secure these dependable marks and spend your time on harder areas.

Capital Structure: topics in the order to study them

  1. 1Capital Structure and Cost of Capital BasicsStart here because WACC, the cost of each source and the idea of a target mix are the language every later theory uses.
  2. 2Modigliani-Miller PropositionsLearn the no-tax and with-tax benchmarks next, since all other theories are described as departures from M&M.
  3. 3Costs of Financial Distress and Static Trade-Off TheoryOnce you know debt adds a tax shield, you can see why distress costs create an optimal leverage point.
  4. 4Pecking Order Theory and SignalingThis adds the information-asymmetry view, which competes with trade-off theory, so study it after the trade-off framework.
  5. 5Target Capital Structure and Practical ConsiderationsFinish with how analysts and managers apply the theory, which pulls together everything above and checks your judgement.

How to prepare Capital Structure

Treat this chapter as a short logic chain rather than a list of facts. Build the chain, then test it with quick questions.

  1. Write out WACC from memory and compute it for two or three sets of weights and costs until the steps are automatic. Remember to use the after-tax cost of debt.
  2. Learn M&M in four lines: no taxes, firm value is unaffected by leverage (Proposition I); with no taxes, rE = r0 + (r0 − rD)(D/E), so cost of equity rises with leverage (Proposition II); with taxes, value rises with debt by the tax shield; with taxes, rE = r0 + (r0 − rD)(1 − t)(D/E), so cost of equity still rises with leverage but more slowly than without taxes, and WACC falls as debt rises.
  3. Draw the trade-off picture: firm value with no debt, rising with the tax shield, then bending down as distress costs grow. Mark the optimal point where marginal benefit equals marginal cost.
  4. Make a two-column table for trade-off theory and pecking order theory: what drives the choice, what the ordering is, and what each predicts about leverage.
  5. Practise direction questions: for each change (higher tax rate, more tangible assets, more volatile earnings), state whether the optimal debt level goes up or down, and why.
  6. Do timed sets of three-option MCQs at about 90 seconds each. For every miss, name the assumption you ignored, such as taxes or distress costs.
  7. Review your error list the day before the exam, and read only the quick revision points on the last day.

Common mistakes in Capital Structure

  • Using the pre-tax cost of debt in WACC.

    Fix: Always check whether a tax rate is given and multiply rD by (1 − t) before weighting.

  • Saying leverage lowers WACC in the no-tax M&M case.

    Fix: Link each statement to its assumption: with no taxes WACC is constant; with taxes WACC falls as debt rises.

  • Mixing up trade-off theory and pecking order theory.

    Fix: Trade-off theory has an optimal leverage target. Pecking order theory has a financing order and no single target.

  • Using book values for the WACC weights when market values are available.

    Fix: Use market values of debt and equity, or the target weights if the question gives them.

  • Treating financial distress costs as only bankruptcy filing fees.

    Fix: Remember indirect costs, such as lost sales, tighter supplier terms and employee departures, which can occur before any filing.

  • Ignoring the direction of the cost of equity when leverage rises.

    Fix: State both effects: more debt raises the required return on equity, while the cheaper after-tax debt lowers WACC in M&M with taxes.

Last-day revision: Capital Structure

  • Capital structure is the mix of debt and equity (and other sources) used to fund the firm.
  • WACC = (E ÷ V) × rE + (D ÷ V) × rD × (1 − t), using market-value weights where possible.
  • The after-tax cost of debt is rD × (1 − t), so debt interest is tax-deductible in the standard setup.
  • M&M Proposition I without taxes: firm value is independent of capital structure.
  • M&M Proposition II without taxes: cost of equity rises as the debt-to-equity ratio rises, and WACC stays constant.
  • M&M with taxes: debt adds value equal to the tax shield, so value of levered firm = value of unlevered firm + tax rate × debt (for permanent debt).
  • Financial distress costs include direct costs such as legal fees and indirect costs such as lost customers and suppliers.
  • Static trade-off theory: the optimal debt level balances the tax shield benefit against the expected cost of financial distress.
  • Pecking order theory: firms prefer internal funds first, then debt, then new equity, because of information asymmetry.
  • Issuing equity can signal that managers think shares are overvalued, which can lower the share price.
  • Target capital structure is the mix management aims for over time, and the actual mix can differ from it in the short run.
  • Factors that support more debt include stable cash flows, tangible assets and a higher tax rate; the opposite factors favour less debt.

Capital Structure practice questions

Capital Structure in other exams

The same ground in other exams, if you are preparing for more than one or want another angle on it.

Capital Structure: frequently asked questions

What is the main idea of capital structure in CFA Level I?

It is about how a firm's mix of debt and equity affects its cost of capital and value. You study M&M, the tax shield, distress costs and behavioural theories that explain real financing choices.

Do I need to memorise many formulas for this chapter?

No. The key formula is WACC with the after-tax cost of debt, plus the M&M value and cost of equity relationships. Most marks come from understanding which way things move and under which assumptions.

How is trade-off theory different from pecking order theory?

Trade-off theory says firms aim for an optimal debt level that balances the tax shield against distress costs. Pecking order theory says firms prefer internal funds, then debt, then new equity, because outsiders know less than managers.

How long should I spend on this chapter?

It is short compared with many other chapters, so a few focused sessions plus practice questions are usually enough. Spend longer if WACC calculations or M&M assumptions still feel shaky.