Discounted Cash Flow: How to Value a Business on Cash

Key Takeaways

• A discounted cash flow model sums the present value of explicit forecast cash flows plus a terminal value that captures all remaining periods after the forecast window.
• Terminal value typically accounts for 60 to 80 percent of total DCF output, Damodaran calls it "the tail that wags the dog."
• Terminal growth must never exceed the risk-free rate; setting it above 4 to 5 percent implies the business eventually grows larger than the economy.
• Mixing firm and equity cash flows with the wrong discount rate, for example FCFE at WACC, produces a meaningless number.

What It Is

A DCF model expresses the value of a business as the sum of two pieces: an explicit forecast of cash flows over a finite window, and a terminal value that captures everything after that window. The explicit period is usually five to ten years, chosen so the firm can plausibly reach a stable growth and margin profile by the end.

There are two common flavors. A firm-value DCF discounts free cash flow to the firm (FCFF) at the weighted average cost of capital (WACC) and arrives at enterprise value. An equity DCF discounts free cash flow to equity (FCFE) or dividends at the cost of equity and arrives directly at equity value. The two approaches should give consistent answers when built correctly.

See Intrinsic Value for the conceptual parent idea. DCF is the mechanical engine behind most intrinsic value estimates.

The Intuition

A dollar arriving ten years from now is worth less than a dollar today, for two reasons. You could have invested today's dollar in a safe asset and earned interest. And future cash flows are uncertain, so you demand extra compensation for the risk of not receiving them. The discount rate bundles both effects into a single number.

The point of building a DCF is not to produce a precise price target. It is to make your assumptions explicit. Growth, margins, reinvestment, and risk all have to sit somewhere on a spreadsheet. When the market disagrees with your output, you can inspect which assumption drives the gap.

How It Works

The general DCF formula for a firm valuation:

Enterprise Value = sum_{t=1..n} [ FCFF_t / (1 + WACC)^t ] + TV_n / (1 + WACC)^n

Where FCFF_t is free cash flow to the firm in year t, WACC is the weighted average cost of capital, n is the length of the explicit forecast, and TV_n is the terminal value at the end of year n.

The Gordon growth shortcut is the most common way to compute terminal value:

TV_n = FCFF_n * (1 + g) / (WACC - g)

Here g is the perpetual growth rate of cash flow. Damodaran's rule is that g can never exceed the risk-free rate, which anchors to long-run nominal GDP growth, roughly 2 to 4 percent for mature economies. Higher values produce a nonsensical claim that the firm grows faster than the economy forever.

Growth itself is not free. In steady state, growth requires reinvestment, so analysts tie the two together:

g = reinvestment rate * ROIC

A model showing 5 percent perpetual growth with zero reinvestment is internally inconsistent.

Worked Example

Suppose a business generated $100 million of free cash flow last year. You project 5 percent growth for five years, then 3 percent perpetually, with a 10 percent discount rate.

Explicit forecast:

Year 1: 105 / 1.10^1 = 95.5
Year 2: 110.25 / 1.10^2 = 91.1
Year 3: 115.76 / 1.10^3 = 86.9
Year 4: 121.55 / 1.10^4 = 83.0
Year 5: 127.63 / 1.10^5 = 79.2
Sum of discounted explicit cash flows = 435.7

Terminal value at the end of year 5:

TV_5 = 127.63 * 1.03 / (0.10 - 0.03) = 1,878.1
PV of TV = 1,878.1 / 1.10^5 = 1,166.0

Enterprise value is 435.7 + 1,166.0 = approximately $1,602 million. Terminal value accounts for roughly 73 percent of that total, a ratio typical of real-world DCFs.

Now stress the inputs. Cut terminal growth from 3 to 2 percent and TV drops to 1,628, pulling enterprise value down about 14 percent. Raise the discount rate from 10 to 11 percent and enterprise value drops another 13 percent. Small changes to r and g swing the answer by double digits. That is not a bug in your model; it is the core feature of DCF.

Common Mistakes

1. Garbage in, garbage out. A DCF is a mechanical calculator wrapped around four or five assumptions. Revenue growth, margins, reinvestment, discount rate, and terminal growth drive almost the entire output. Small errors on any of these compound. Always publish a sensitivity table showing how value responds as you flex each input a point or two.

2. Letting the terminal value swallow everything. Damodaran calls terminal value "the tail that wags the dog" because it often captures 60 to 80 percent of total value. If your TV share is above 85 percent, your explicit forecast is not really doing any work. Extend the forecast window, sanity-check the terminal growth rate, or cross-check with an exit-multiple terminal value.

3. Mixing up cash flows and discount rates. Firm cash flows (FCFF) must be discounted at WACC. Equity cash flows (FCFE or dividends) must be discounted at the cost of equity. Mixing them, for example discounting FCFE at WACC, produces a number that is meaningless. The same rule applies to currency and to nominal versus real terms.

4. Extrapolating high growth forever. No company grows faster than the economy permanently. Damodaran caps terminal growth at the risk-free rate. Setting g at 6 or 7 percent in a US-dollar model implies the business eventually becomes larger than the economy itself, which is impossible.

5. Forgetting reinvestment. If a firm grows FCFF at 5 percent forever with no reinvestment, its implied return on invested capital is infinite. Tie growth to a reinvestment rate and an ROIC you can defend. Otherwise you are claiming free growth.

6. Skipping scenario analysis. A single point estimate hides the model's fragility. Build base, bull, and bear cases with clearly stated assumptions. If only the bull case clears today's price, that tells you something important about margin of safety.

7. Circular reasoning with the discount rate. Backing the cost of equity out of the current market price, then using it to value the stock, just returns the market's own answer. Anchor r to long-run data and to fundamentals, not to whatever the tape is doing this week.

Frequently Asked Questions

Q: What is discounted cash flow in simple terms? Discounted cash flow is a method for estimating what a business is worth today based on the cash it will generate in the future. Each future cash flow is reduced, discounted, by a rate that reflects how risky and distant it is.

Q: How does discounted cash flow affect investment decisions? A DCF forces investors to make assumptions explicit: growth rate, margins, reinvestment, and risk all sit on a spreadsheet. When the market price diverges from the DCF output, investors can identify exactly which assumption drives the gap.

Q: What is a real-world example of discounted cash flow? A business producing $100 million of free cash flow, growing 5% for five years then 3% forever, discounted at 10%, has an enterprise value of roughly $1,602 million, with terminal value accounting for about 73% of that total.

Q: How can investors use discounted cash flow practically? Always publish a sensitivity table showing how value changes as you flex growth and discount rates by one or two percentage points. A single point estimate hides the model's fragility; a range of scenarios reveals it.

Q: How is discounted cash flow different from comparable company analysis? DCF derives value from the company's own fundamentals, cash flows and risk. Comparable company analysis anchors value to what peers are currently trading at in the market, which embeds whatever optimism or pessimism the market holds at that moment.

Sources

1. Damodaran, A. "Basics of Discounted Cash Flow Valuation." NYU Stern. https://pages.stern.nyu.edu/~adamodar/pdfiles/basics.pdf
2. Damodaran, A. "Closure in Valuation: Estimating Terminal Value." NYU Stern. https://pages.stern.nyu.edu/~adamodar/pdfiles/papers/termvalue.pdf
3. Damodaran, A. "Myth 5.5: The Terminal Value Ate My DCF." Musings on Markets. https://aswathdamodaran.blogspot.com/2016/11/myth-55-terminal-value-ate-my-dcf.html
4. CFA Institute. "Free Cash Flow Valuation." Refresher Readings. https://www.cfainstitute.org/insights/professional-learning/refresher-readings/2026/free-cash-flow-valuation
5. Corporate Finance Institute. "Discounted Cash Flow DCF Formula." https://corporatefinanceinstitute.com/resources/valuation/dcf-formula-guide/
6. Corporate Finance Institute. "DCF Terminal Value Formula." https://corporatefinanceinstitute.com/resources/financial-modeling/dcf-terminal-value-formula/

Disclaimer

This article is educational content only and is not financial advice. Nothing here is a recommendation to buy, sell, or hold any security. Consult a licensed advisor before making investment decisions.