DCF Interview Questions: 15 Chained Follow-Ups (and How to Answer Every Link)

You nailed "walk me through a DCF." Great. Now the interviewer leans in and asks, "Why unlevered free cash flow?" Then, "How would you get beta for a private company?" Then, "Is it a problem that terminal value is most of your valuation?"

That's how DCF questions really work in interviews: as a chain. Each answer you give opens the door to the next question. This post walks you through 15 of the most common follow-ups in the order they tend to come up, with the reasoning and the numbers you need to keep going without freezing.

How the Chain Usually Starts

Almost every DCF conversation opens with the same prompt: "Walk me through a DCF."

Your short answer should be something like this:

"You project a company's unlevered free cash flows over roughly five to ten years, calculate a terminal value for everything after that, and discount both back to today using the WACC. That gives you enterprise value. Then you subtract net debt and other claims to get equity value, and divide by diluted shares for an implied share price."

Keep it to 30 seconds. The interviewer will pull on whichever thread they want. Here's where they usually pull.

Part 1: The Cash Flows

Follow-Up 1: "Why use unlevered free cash flow instead of levered?"

Unlevered free cash flow (UFCF) is the cash available to all capital providers, both debt and equity holders, before any interest payments.

That makes it capital-structure neutral. Two identical businesses with different amounts of debt should have the same enterprise value, and UFCF gives you that.

The key logic to say out loud:

• UFCF belongs to everyone, so you discount it at a rate that reflects everyone (WACC)
• The result is enterprise value
• If you used levered FCF, you'd discount at the cost of equity and land directly on equity value

Matching is the whole game: the cash flow, the discount rate, and the value you get must all refer to the same group of investors.

Follow-Up 2: "How do you calculate unlevered free cash flow?"

The standard formula:

UFCF = EBIT × (1 − tax rate) + D&A − CapEx − increase in net working capital

Here's a quick worked example:

Notice you start from EBIT, not net income. Net income is already after interest, which would sneak capital structure back into the number.

Follow-Up 3: "Why does an increase in working capital reduce cash flow?"

Because growing working capital means cash gets tied up in the business.

Say accounts receivable rise by $10m this year. You booked that revenue, but customers haven't paid you yet. Your income statement looks good, but the cash isn't in the bank.

Same with inventory: buying more stock uses cash before you sell anything. On the flip side, if accounts payable increase, you're holding onto cash you owe suppliers, which helps cash flow.

A clean way to say it: "An asset going up uses cash, a liability going up provides cash."

Follow-Up 4: "How many years do you project, and why?"

Usually five to ten years. The goal is to project until the company reaches a steady state, meaning its growth and margins have settled into something sustainable.

• A mature consumer goods company might need only five years
• A fast-growing tech company might need ten, because it's nowhere near steady state in year five

The reason it matters: the terminal value formula assumes stable growth forever. If you stop projecting while the company is still growing 20% a year, your terminal value is built on a shaky foundation.

Part 2: The Discount Rate

Follow-Up 5: "Why do you discount at WACC?"

Because UFCF goes to both debt and equity holders, so the discount rate needs to reflect what both groups require.

WACC is a blend of the cost of equity and the after-tax cost of debt, weighted by how much of each the company uses. It's the return the company must earn to satisfy all its investors.

Follow-Up 6: "Walk me through calculating WACC."

WACC = (E / (D + E)) × Cost of equity + (D / (D + E)) × Cost of debt × (1 − tax rate)

Use market values for the weights where possible, not book values.

Worked example:

• Equity weight: 70%, debt weight: 30%
• Cost of equity: 10.6%
• Pre-tax cost of debt: 6%, tax rate 25%, so after-tax cost of debt = 6% × 0.75 = 4.5%

WACC = 0.70 × 10.6% + 0.30 × 4.5% = 7.42% + 1.35% = 8.77%, call it roughly 8.8%.

The interviewer will almost certainly ask where that 10.6% came from. Which brings us to...

Follow-Up 7: "How do you calculate the cost of equity?"

Most banks use the Capital Asset Pricing Model (CAPM):

Cost of equity = Risk-free rate + Beta × Equity risk premium

Using our numbers:

• Risk-free rate: 4% (typically the yield on a long-term government bond)
• Beta: 1.2
• Equity risk premium: 5.5%

Cost of equity = 4% + 1.2 × 5.5% = 4% + 6.6% = 10.6%

Beta measures how sensitive the stock is to the overall market. A beta of 1.2 means the stock tends to move more than the market, so investors demand a higher return.

Follow-Up 8: "What if the company is private? Where does beta come from?"

This is where a lot of candidates stumble. A private company has no stock price, so you can't measure its beta directly.

Instead, you borrow beta from comparable public companies, but you have to adjust for leverage first:

1. Unlever each comp's beta to strip out the effect of their debt
2. Take the average or median unlevered beta
3. Relever it using your company's target capital structure

The formula most banks use:

Levered beta = Unlevered beta × [1 + (1 − tax rate) × (D/E)]

Worked example: comps have an average levered beta of 1.25 and a D/E of 0.5, tax rate 25%.

• Unlever: 1.25 / [1 + 0.75 × 0.5] = 1.25 / 1.375 = 0.909
• Relever at your company's D/E of 30/70 = 0.429: 0.909 × [1 + 0.75 × 0.429] = 0.909 × 1.321 = 1.20

And there's the 1.2 we plugged into CAPM. Showing that link in an interview is a strong signal you actually understand the model.

Follow-Up 9: "Why is the cost of debt lower than the cost of equity?"

Two main reasons:

• Priority: debt holders get paid before equity holders, and in bankruptcy they're ahead in line. Less risk means a lower required return
• Tax shield: interest is generally tax-deductible, so the after-tax cost is even lower (6% pre-tax became 4.5% in our example)

Equity holders get whatever is left over, which is riskier, so they demand more.

Follow-Up 10: "So should a company just keep adding debt to lower its WACC?"

Classic trap. The answer is no, only up to a point.

At first, swapping equity for cheaper debt does lower WACC. But as debt piles up:

• Equity becomes riskier, so the cost of equity rises (you just saw how leverage increases beta)
• Lenders charge higher rates as default risk grows, so the cost of debt rises too
• Eventually the risk of financial distress outweighs the tax benefit

So WACC typically falls, bottoms out at some optimal level of leverage, and then starts rising again. Saying "it's U-shaped" is a nice way to wrap it up.

Part 3: Terminal Value

Follow-Up 11: "How do you calculate terminal value?"

Two methods:

1. Perpetuity growth (Gordon Growth) method

TV = Final year UFCF × (1 + g) / (WACC − g)

Example: final year UFCF of $80m, long-term growth of 2.5%, WACC of 8.8%:

TV = 80 × 1.025 / (0.088 − 0.025) = 82 / 0.063 = about $1,302m

2. Exit multiple method

Apply a multiple (usually EV/EBITDA) from comparable companies to final year EBITDA. If year 5 EBITDA is $150m and comps trade at 8.5x, TV = $1,275m.

Then discount the terminal value back to today. At 8.8% over five years, the discount factor is 1.088^5 ≈ 1.525, so the present value of our $1,302m TV is roughly $854m.

Pro tip: cross-check the two methods. Our perpetuity TV of $1,302m implies an exit multiple of about 8.7x EBITDA ($1,302m / $150m). If that implied multiple were 25x for a mature business, you'd know your growth assumption was off.

Follow-Up 12: "What growth rate would you use? Why not 8%?"

The terminal growth rate represents growth forever. No company can outgrow the overall economy indefinitely, or it would eventually become the economy.

So you typically use something at or below long-term nominal GDP growth, often in the 2% to 3% range for a mature company in a developed market.

And there's a mathematical reason too: g must be lower than WACC. If g equals WACC, the denominator is zero. If g exceeds WACC, you get a negative value. Either way, the formula breaks.

Follow-Up 13: "Terminal value is 75% of your enterprise value. Is that a problem?"

Not necessarily. It's very common for terminal value to make up the majority of a DCF's value, especially for growing companies whose biggest cash flows come later.

But it does mean your valuation is highly sensitive to a few assumptions: the terminal growth rate, the exit multiple, and WACC.

A strong answer shows you know how to manage that:

• Run sensitivity tables on WACC and terminal growth (or exit multiple)
• Cross-check the implied multiple against comps, like we did above
• Consider extending the projection period if the company isn't at steady state yet

Part 4: Getting to a Share Price

Follow-Up 14: "How do you get from enterprise value to share price?"

Enterprise value is the value of the core business to all investors. To get to what belongs to shareholders:

Equity value = Enterprise value − Debt − Preferred stock − Noncontrolling interest + Cash

Then divide by diluted shares outstanding.

Worked example:

• Enterprise value: $1,200m
• Debt: $300m
• Cash: $50m
• Equity value: 1,200 − 300 + 50 = $950m
• Diluted shares: 50m
• Implied share price: $19.00

Expect a mini follow-up here: "How do you calculate diluted shares?" Mention the treasury stock method for options and warrants, and note that since dilution depends on the share price, there's a slight circularity, since the implied price itself determines which options are in the money.

Follow-Up 15: "What would increase the value more: 10% higher cash flows or a 1% lower discount rate?"

The interviewer wants to see you think about sensitivity, not just recite formulas.

Use the perpetuity logic as a shortcut. Value is roughly cash flow / (WACC − g).

• 10% higher cash flows: value rises about 10%, since cash flow sits in the numerator
• 1% lower WACC: the spread goes from 8.8% − 2.5% = 6.3% to 7.8% − 2.5% = 5.3%. Value rises by 6.3 / 5.3 − 1 ≈ 19%

So in this example, the discount rate change wins, and that's typical when terminal value dominates the valuation.

The nuanced answer adds: "It depends on the starting numbers. The lower the gap between WACC and growth, the more powerful a change in the discount rate becomes." That one sentence shows real understanding.

How to Practice the Chain

Knowing the 15 answers isn't enough. You need to handle them in sequence, under pressure. A few tips:

• Practice out loud with a friend who interrupts you after every answer with "why?"
• Use the same numbers throughout, like we did here. Interviewers love it when your beta, WACC, and terminal value all connect
• Keep each answer to 30 to 60 seconds. Short answers invite the next question; rambling answers invite trouble
• When stuck, go back to matching. Cash flow, discount rate, and resulting value must all refer to the same investors. That principle answers a surprising number of follow-ups

The interviewer isn't trying to catch you on trivia. They're testing whether you understand why each piece of the DCF exists. Master the chain, and the question "walk me through a DCF" stops being scary and starts being your chance to shine.