DCF Model: Step-by-Step Build Guide

A DCF model values a company on its own projected cash flows, discounted to today at the weighted average cost of capital. Building one takes six steps: forecast revenue and margins, convert to unlevered free cash flow, calculate a terminal value, discount everything back at WACC, bridge from enterprise value to equity value, and sensitivity-test the assumptions that dominate the answer. The mechanics are learnable in an afternoon; the skill is setting assumptions you can defend. This guide walks each step with a worked example, and if you need the interview-answer version instead, that lives in walk me through a DCF.

TL;DR

• A DCF model has six steps: forecast operations, build unlevered FCF, terminal value, discount at WACC, EV-to-equity bridge, sensitivity.
• Unlevered FCF = EBIT × (1 − tax) + D&A − CapEx − change in NWC; it belongs to all capital providers, so it discounts at WACC.
• Terminal value typically contributes 60 to 80 percent of the answer, which is why the perpetuity growth rate and exit multiple get grilled.
• The output is a range, not a point: the sensitivity table is part of the deliverable, not an appendix.
• Worked example below: a 100-million-dollar-EBIT business prices near 1.7 billion enterprise value on reasonable assumptions.

What is a DCF model?

A DCF model is a spreadsheet that projects a company's unlevered free cash flow over an explicit forecast period (usually five to ten years), estimates the value of everything beyond that window as a terminal value, and discounts the whole stream back to the present. Corporate Finance Institute compresses it to one sentence: "build a 5-year forecast of unlevered free cash flow based on reasonable assumptions, calculate a terminal value with an exit multiple approach, and discount all those cash flows to their present value using the company's WACC." Unlike a comps analysis, the output does not depend on where peers trade today: it is intrinsic value, for better and for worse.

Step 1: How do you forecast revenue and margins?

Start from the income statement, not the cash flow statement. Project revenue using the driver that fits the business (volume × price, subscribers × ARPU, or simple growth rates off history), then apply margin assumptions to get to EBIT. Five years is the standard explicit window; extend only if the company genuinely needs longer to reach steady state. The discipline is defensibility: every growth and margin number should trace to history, industry data, or a stated driver, not a round number. How to forecast cash flows in a DCF covers the forecasting layer in depth.

Step 2: How do you build unlevered free cash flow?

From each forecast year's EBIT, tax it, add back non-cash charges, and subtract reinvestment:

$FCF = EBIT \times (1 - T) + D\&A - CapEx - \Delta NWC$

Worked example with a company at 100 million dollars of EBIT, a 25 percent tax rate, 20 million of D&A, 30 million of CapEx, and NWC growing by 10 million a year: NOPAT is 100 × 0.75 = 75; add back 20 of D&A for 95; subtract 30 of CapEx and 10 of NWC growth; unlevered FCF is 55 million dollars per year. Grow EBIT modestly and the FCF line scales with it. Because this cash belongs to lenders and shareholders together, it is the version that pairs with WACC; the levered/unlevered distinction is covered in unlevered vs levered free cash flow.

Step 3: How do you calculate terminal value?

Terminal value captures every year after the forecast ends, and there are two methods. The Gordon growth method assumes perpetual growth at rate g: TV = FCF_final × (1 + g) / (WACC − g), with g capped near long-run GDP growth, roughly 1 to 3 percent. The exit multiple method applies a market multiple, usually EV/EBITDA, to the final-year metric. CFI notes it is the more common approach in banking. Compute both and cross-check: if Gordon implies an 18x exit EBITDA multiple while peers trade at 9x, your growth rate is quietly too high. Full mechanics in terminal value explained.

Step 4: How do you discount and bridge to equity?

Discount each year's FCF and the terminal value at WACC, dividing each by (1 + WACC)^t, and sum the pieces for enterprise value. Then bridge to equity: subtract net debt, preferred stock, and noncontrolling interest; divide by diluted shares for an implied price per share. The enterprise value vs equity value guide and the EV bridge component walkthrough cover the claims waterfall.

Continuing the worked example: five years of FCF growing 55 to 70, WACC of 9 percent, g of 2.5 percent. Terminal value is roughly 70 × 1.025 / 0.065 ≈ 1,104 million, discounted back ≈ 717. Explicit-period PV adds roughly 230. Enterprise value ≈ 947 million; with 200 of net debt, implied equity value ≈ 747 million dollars.

Step 5: How do you sensitivity-test the model?

You present a range, because the model is honest about its own fragility. The standard output is a two-way table flexing WACC against terminal growth (or exit multiple):

EV in millions for the worked example. A one-point move in either assumption swings the answer by roughly 10 percent, and TV dominates the total. That is exactly what DCF sensitivity analysis is for, and why interviewers ask which two inputs you would flex first.

What do interviewers probe in a DCF model?

They probe the same three places every time: why unlevered FCF pairs with WACC (cash flow investor group must match the discount rate's investor group), why terminal value dominates (and how you defend g), and how each assumption moves the answer. The answers live in DCF interview questions. If you want a structured rep on the whole sequence rather than reading it again, the drill set below runs the actual questions.

Practice inside this guide

DCF interview practice

Question 1 of 1

Why does a DCF discount unlevered free cash flow at WACC rather than at the cost of equity?

Your answer

Reveal model structure

Frequently Asked Questions

How many years should a DCF forecast?

Five to ten years is standard, with five the common default per CFI. Forecast until the business reaches a steady, normalized state; a high-growth company can justify the longer window so its growth matures before perpetuity assumptions take over.

What is the difference between a DCF model and a comps analysis?

A DCF values the company on its own projected cash flows, giving intrinsic value independent of market prices. Comps value it relative to where similar companies trade: relative value, market-dependent. Bankers run both and compare them on a football field rather than trusting either alone.

Why is WACC the right discount rate for a DCF model?

Unlevered free cash flow belongs to all capital providers, so it must be discounted at the blended rate all providers require: WACC. Discounting unlevered flow at the cost of equity understates value; the matched pairing is the rule. See WACC explained for the input build.

What is the biggest mistake in a DCF model?

Letting terminal value carry unjustified assumptions. A perpetuity growth rate above long-run GDP growth, or an exit multiple above what peers trade at, inflates 60 to 80 percent of the answer invisibly. Cross-check Gordon against the implied exit multiple every time.

Do you include stock-based compensation in a DCF?

Treat it as a real expense in the FCF build (do not add it back like D&A) and let dilution come through the share count in the EV-to-equity bridge. Double-counting it in both places is a common modeling error.

Sources

• Corporate Finance Institute, "Walk Me Through a DCF": https://corporatefinanceinstitute.com/resources/career/walk-me-through-a-dcf/ (checked September 2026)
• Wall Street Prep, "Walk Me Through a DCF": https://www.wallstreetprep.com/knowledge/walk-me-through-dcf/ (checked September 2026)
• Mergers & Inquisitions, "DCF Model: Full Guide": https://mergersandinquisitions.com/dcf-model/ (checked September 2026)
• Financial Edge, "Walk Me Through a DCF (5 Steps)": https://www.fe.training/free-resources/financial-modeling/walk-me-through-a-dcf-5-steps/ (checked September 2026)