DCF Interview Questions and Answers
The DCF interview questions bankers actually ask, from why unlevered FCF to terminal value methods and sensitivities, each with a tight model answer.
Jun 9, 2026 · 8 min read
DCF interview questions probe whether you understand the mechanics behind the model or just memorized a walkthrough. After you answer "walk me through a DCF," the interviewer drills into the assumptions: why you use unlevered free cash flow, why you discount at WACC, how you build terminal value, and where the model breaks. Wall Street Prep's interview guide lists 18 distinct DCF questions an analyst should expect. The follow-ups are where most candidates fall apart, because they reveal whether you grasp the logic or just the steps. This drill covers the questions that come up most, each with a model answer you can deliver fast.
TL;DR
- A DCF discounts unlevered free cash flow at WACC to get enterprise value, then bridges to equity value via net debt.
- Use unlevered FCF because it's capital-structure neutral, representing cash available to all investors before financing.
- Terminal value often drives roughly three-quarters of total enterprise value, per Wall Street Prep.
- The two terminal value methods are Gordon growth (perpetuity) and exit multiple; bankers calculate both.
- Perpetuity growth typically runs 1% to 3%, in line with long-run inflation expectations.
What is a DCF interview question testing?
A DCF interview question tests whether you understand intrinsic valuation: that a company is worth the present value of the cash it will generate, discounted for risk and time. Interviewers want logic, not recitation. They probe the assumptions because that's where judgment lives. The model itself is mechanical; the defensibility of its inputs is what separates a strong candidate from a memorizer. Expect rapid follow-ups that change one variable and ask how the output moves. For the full step-by-step structure, see walk me through a DCF. This article is the Q&A drill that builds on that walkthrough, focusing on the follow-ups interviewers use to find the edge of your understanding.
Why do you use unlevered free cash flow?
You use unlevered free cash flow because it represents the cash available to all capital providers, both debt and equity holders, before any financing decisions. That makes the analysis capital-structure neutral and produces enterprise value directly. Unlevered FCF starts from EBIT, taxes it to get NOPAT, adds back non-cash charges like depreciation and amortization, then subtracts capital expenditures and the change in net working capital. Because it excludes interest, it isn't distorted by how the company chooses to finance itself. A levered DCF, by contrast, projects free cash flow to equity, discounts at the cost of equity, and arrives directly at equity value. The unlevered approach is the IB standard because it lets you value the business independently of its capital structure.
Why do you discount at WACC?
You discount unlevered free cash flow at WACC because the weighted average cost of capital reflects the blended required return of all capital providers, which matches the cash flows you're discounting. Unlevered FCF belongs to both lenders and shareholders, so the discount rate must represent both. WACC weights the after-tax cost of debt and the cost of equity by their proportions in the capital structure. The cost of equity comes from CAPM, where the equity risk premium has historically ranged from about 4% to 6%, per Wall Street Prep. If you discounted unlevered cash flows at the cost of equity alone, you'd overstate the discount rate and understate value. For the full mechanics, see WACC explained.
How do you calculate terminal value?
There are two standard terminal value methods, and most bankers calculate both to cross-check. The Gordon growth method assumes cash flows grow at a constant rate forever, with that long-term growth rate typically running 1% to 3%, in line with inflation. The exit multiple method applies a market multiple, usually EV/EBITDA, to the final forecast-year metric. The terminal value matters enormously: it can contribute roughly three-quarters of the implied valuation, per Wall Street Prep, which is exactly why interviewers press on it. A common trap is choosing a perpetuity growth rate above long-run GDP growth, which implies the company eventually outgrows the entire economy.
| Method | Assumption | Common input | Watch out for |
|---|---|---|---|
| Gordon growth | Constant perpetual growth | g of 1% to 3% | g exceeding long-run GDP growth |
| Exit multiple | Sale at a market multiple | EV/EBITDA from comps | Multiple implying an unrealistic growth rate |
What is the difference between FCFF and FCFE?
Free cash flow to firm (FCFF) is unlevered cash flow available to all investors before financing, while free cash flow to equity (FCFE) is levered cash flow available only to shareholders after debt service. FCFF is discounted at WACC and yields enterprise value; FCFE is discounted at the cost of equity and yields equity value directly. The practical difference is interest and net debt issuance. FCFF excludes the effect of interest payments entirely, keeping it capital-structure neutral. FCFE subtracts after-tax interest and adds net borrowing, so it reflects what's actually left for equity holders. Banks default to the FCFF (unlevered) approach because it isolates operating value from financing choices, which is cleaner for comparison.
How do you bridge from enterprise value to equity value?
You bridge from enterprise value to equity value by subtracting net debt, which is total debt minus cash and equivalents. A DCF on unlevered cash flows produces enterprise value, the value of the whole business to all capital providers. To isolate what belongs to shareholders, you strip out the claims that rank ahead of common equity: debt, preferred stock, and noncontrolling interests, while adding back cash. The result is equity value, which you divide by fully diluted shares outstanding for an implied per-share price. This bridge is one of the most common follow-ups in any interview, often asked as a standalone question. For a full breakdown, see enterprise value vs equity value.
What are the biggest weaknesses of a DCF?
The biggest weakness of a DCF is its extreme sensitivity to assumptions, particularly the terminal value and the discount rate. Because terminal value can drive roughly three-quarters of the total, a small change in the perpetuity growth rate or exit multiple swings the valuation dramatically. The discount rate is similarly powerful: a change of half a percentage point in WACC materially moves the answer. A DCF is also only as good as its forecast, and projecting cash flows accurately beyond two or three years is genuinely hard. This is why bankers run sensitivity tables across WACC and terminal growth, and why a DCF is usually one of several methods, triangulated against comparable companies and precedent transactions rather than used alone.
Frequently Asked Questions
Why not use the cost of equity to discount unlevered cash flows?
Because the cost of equity reflects only the return shareholders require, while unlevered cash flows belong to both debt and equity holders. Discounting unlevered FCF at the cost of equity overstates the discount rate and understates value. The rate must match the cash flow: WACC for unlevered, cost of equity for levered.
What is the mid-year convention in a DCF?
The mid-year convention assumes cash flows arrive evenly throughout the year rather than all at year-end, so you discount each year's cash flow using a half-year offset. It slightly increases present value because cash is received sooner on average. Interviewers ask it to test whether you understand the timing mechanics, not just the formula.
When is a DCF an inappropriate valuation method?
A DCF is inappropriate when cash flows are highly unpredictable or negative for the foreseeable future, such as for early-stage startups, pre-revenue biotech, or distressed companies. It also struggles for financial institutions, where interest is core to operations and the unlevered framework breaks down. In those cases bankers lean on comparable companies or specialized methods.
Why does the perpetuity growth rate have to stay low?
Because a company can't grow faster than the overall economy forever. If your perpetuity growth rate exceeds long-run GDP growth, you're implying the business eventually becomes larger than the entire economy, which is impossible. That's why the rate typically sits between 1% and 3%, anchored to long-run inflation expectations.
How do you sensitize a DCF?
You build a two-way data table that flexes the two assumptions with the most impact, usually WACC and the terminal growth rate (or exit multiple), and show the resulting range of implied values. This produces a valuation range rather than a false-precision single number and demonstrates you understand where the model is fragile.
Sources
- Wall Street Prep: DCF Model Interview Questions (checked June 2026)
- Mergers & Inquisitions: Investment Banking Interview Questions and Answers (checked June 2026)
- Corporate Finance Institute: Enterprise Value vs Equity Value (checked June 2026)
- Wall Street Oasis: Walk Me Through a DCF (checked June 2026)