How to Answer DCF Questions in Investment Banking Interviews

A discounted cash flow analysis, or DCF, estimates a company’s intrinsic value based on the cash it is expected to generate in the future. The central idea is that a dollar received later is worth less than a dollar received today, so projected cash flows must be discounted back to their present value.

In most investment banking interviews, you will discuss an unlevered DCF. This approach values the company’s core operations using unlevered free cash flow, which is cash flow available to both debt and equity investors. Discounting those cash flows by the weighted average cost of capital, or WACC, produces enterprise value.

A DCF is different from relative valuation methods such as comparable companies and precedent transactions. Those methods use market or transaction valuation multiples, while a DCF relies primarily on the company’s projected financial performance and assumptions about risk and long-term growth. Interviewers expect you to understand both the theoretical distinction and the practical mechanics.

The classic interview question is, “Walk me through a DCF.” A strong answer should be organized, concise, and delivered in the correct sequence. Start with the operating projections, move through free cash flow and discounting, calculate terminal value, and finish with the bridge from enterprise value to equity value.

You should usually be able to give the initial walkthrough in roughly one to two minutes. Do not interrupt the structure to explain every formula in detail. The interviewer can choose which areas to explore through follow-up questions.

1. Project the company’s income statement and relevant cash flow items over a forecast period, commonly around five years, although the period varies by company and situation.
2. Calculate unlevered free cash flow as EBIT × (1 − tax rate) + depreciation and amortization − capital expenditures − the increase in net working capital. Include other relevant operating adjustments when appropriate.
3. Calculate WACC using the company’s target capital structure, cost of equity, after-tax cost of debt, and any other material sources of capital.
4. Discount each projected unlevered free cash flow to its present value using WACC. If cash flow is assumed to arrive throughout the year, a mid-year convention may be used instead of year-end discounting.
5. Estimate terminal value using either the perpetuity growth method or the exit multiple method, then discount terminal value to present value.
6. Add the present values of the forecast-period cash flows and terminal value to calculate enterprise value.
7. Bridge from enterprise value to equity value by subtracting debt and debt-like claims, adding cash and non-operating assets, and making other relevant adjustments. Divide by diluted shares outstanding if an implied share price is required.

Interviewers frequently test why each item appears in unlevered free cash flow. Begin with EBIT, or earnings before interest and taxes, because an unlevered DCF values operations before considering how the company is financed. Apply taxes to EBIT to estimate net operating profit after tax.

Depreciation and amortization are added back because they reduce accounting earnings but are non-cash expenses in the current period. Capital expenditures are subtracted because purchasing or maintaining long-term assets requires cash. An increase in net working capital is also subtracted because more cash is tied up in operating assets such as inventory and accounts receivable, net of operating liabilities such as accounts payable.

Interest expense is not subtracted in unlevered free cash flow. Financing costs are already reflected in WACC, and subtracting interest would mix operating value with capital structure and effectively count the impact of debt twice.

Be ready for variations. Some companies have stock-based compensation, restructuring costs, operating lease adjustments, deferred taxes, or other items requiring judgment. Explain the economic principle: include recurring operating cash flows and remain consistent between the cash flow definition, discount rate, and enterprise-to-equity bridge.

WACC represents the blended required return of the company’s capital providers. In a basic structure, WACC equals the equity weight multiplied by the cost of equity, plus the debt weight multiplied by the after-tax cost of debt. Market values, rather than book values, are generally used for the capital structure weights.

The cost of equity is often estimated with the Capital Asset Pricing Model: risk-free rate + beta × equity risk premium. Beta measures the sensitivity of a company’s equity returns to broader market returns. For a private company or a company with an unreliable beta, you may unlever comparable-company betas to remove their capital structures, take a representative estimate, and relever it using the subject company’s target capital structure.

The after-tax cost of debt is the company’s pre-tax borrowing cost multiplied by one minus the marginal tax rate, assuming the interest tax shield is usable. If preferred stock or another material source of capital exists, it may need a separate component in WACC.

Terminal value captures the value of cash flows after the explicit forecast period. Under the perpetuity growth method, terminal value equals final-year unlevered free cash flow × (1 + perpetual growth rate) divided by (WACC − perpetual growth rate). The growth rate must be below WACC and should be supportable for a mature business over the very long term.

Under the exit multiple method, you apply a selected valuation multiple, such as enterprise value to EBITDA, to a terminal-year financial metric. The multiple should be supported by comparable companies, the company’s expected maturity, and market conditions. In practice, bankers may use one method as the primary approach and the other as a cross-check.

Many DCF questions test directional understanding. If WACC increases, present value generally decreases because future cash flows are discounted more heavily. If the perpetual growth rate increases, terminal value generally rises. Higher capital expenditures or a larger increase in net working capital reduce free cash flow and valuation, all else equal.

If depreciation increases by itself, the effect is more nuanced than “valuation increases.” Depreciation lowers taxable income and creates a tax shield, but it is added back because it is non-cash. However, higher depreciation may be associated with higher historical or future capital expenditures. State the assumptions behind your answer rather than treating linked operating items as unrelated.

You may also be asked why an unlevered DCF uses WACC while a levered DCF uses the cost of equity. Unlevered free cash flow belongs to all capital providers, so it is discounted at the blended required return. Levered free cash flow is calculated after interest and mandatory debt payments and belongs only to equity holders, so it is discounted at the cost of equity.

Another common question is how to value a company with negative cash flow. You can still use a DCF if the company is expected to produce positive cash flow later and the forecasts are credible. You may need a longer explicit forecast period before applying a terminal value. If cash flow never reaches a stable, sustainable level, a standard DCF becomes difficult to defend.

• Higher WACC generally means lower valuation.
• Higher perpetual growth generally means higher valuation.
• Higher capital expenditures generally mean lower free cash flow and valuation.
• An increase in net working capital is generally a use of cash.
• Using a lower exit multiple generally reduces terminal value.
• Holding enterprise value constant, more debt generally means lower equity value.

Start with the direct answer, then explain the reason. If asked what happens when WACC rises, say that valuation falls before discussing discount factors and terminal value. Interviewers should not have to search through your response for the conclusion.

Keep your terminology consistent. Do not discount unlevered free cash flow using the cost of equity, confuse enterprise value with equity value, or subtract interest after starting with EBIT and also use WACC. These mistakes indicate that the formulas were memorized without understanding who receives each cash flow.

When a question lacks necessary information, state a reasonable assumption. For example, the effect of lower taxes may depend on whether the company can use its tax benefits and whether other variables remain constant. A qualified answer is stronger than false certainty.

Practice in layers. First, master the short DCF walkthrough. Next, learn the purpose of every formula component. Then work through numerical examples and sensitivity questions without notes. Finally, practice aloud so that your response remains structured under pressure. The objective is not to recite the longest possible answer; it is to show that you can connect accounting, cash flow, risk, and valuation logically.

• Give the conclusion first.
• Explain the economic reason, not only the formula.
• State what you are holding constant.
• Flag situations in which the answer depends on company-specific facts.
• Stop after answering the question and let the interviewer choose the follow-up.

• A DCF values a company by discounting projected cash flows and terminal value to the present.
• In an unlevered DCF, calculate unlevered free cash flow, discount it using WACC, and derive enterprise value.
• Understand why each free cash flow adjustment is made, especially taxes, non-cash charges, capital expenditures, and working capital.
• Be prepared to explain both terminal value methods and defend the assumptions behind them.
• For follow-ups, answer directly, state what remains constant, and explain the economic logic.

How detailed should my DCF walkthrough be in an interview?

Aim for a clear initial explanation of roughly one to two minutes. Cover projections, unlevered free cash flow, WACC, present value, terminal value, enterprise value, and the bridge to equity value. Save detailed formulas and special cases for follow-up questions.

Which terminal value method should I mention first?

Either the perpetuity growth method or exit multiple method is acceptable unless the interviewer specifies a preference. Explain both and note that the appropriate primary method depends on the company, industry, and assignment. The other method can serve as a cross-check.