Free Cash Flow & Working Capital
Free cash flow = operating cash flow minus capital expenditures. It's the cash a business generates after maintaining its asset base — the raw material of valuation.
Working capital (receivables + inventory − payables) is a hidden cash engine. Reducing days-sales-outstanding by 10 days can release more cash than a year of cost cutting.
EBITDA is a useful shorthand but ignores working capital, capex, taxes and interest — treat it as a starting point, never the answer.
The cash conversion cycle (DIO + DSO − DPO) measures how many days each dollar is trapped in operations. Shorter is stronger.
Capital expenditures (capex) are cash investments in long-lived assets, such as equipment, buildings or software, to maintain or expand operating capacity. Operating cash flow is cash generated or consumed by normal business operations; subtracting capex gives free cash flow under the definition used here. Revenue measures sales rather than cash remaining, while dividends are distributions to shareholders, not capital expenditures.
Extending supplier payment terms from 30 to 45 days increases Days Payables Outstanding (DPO), shortening the cash conversion cycle and retaining cash longer. Even when suppliers agree, the longer wait can strain their liquidity, damage relationships or impair their ability to deliver reliably. These risks differ from breaching agreed terms but still warrant assessment. The extension does not directly change customer collection days or automatically increase net profit margin—the share of revenue retained as net income—and the resulting cash release is one-time, not an annually repeatable benefit.
EBITDA means earnings before interest, taxes, depreciation and amortization; it is an earnings measure, not cash available to investors. Enterprise valuation values the operating business for both debt and equity investors and generally uses unlevered free cash flow: after-tax operating profit plus noncash depreciation and amortization, minus capital expenditures and increases in operating working capital. This measure captures taxes, asset investment and cash tied up in operations that EBITDA omits, making it a more rigorous basis for valuation. Unlevered FCF excludes financing interest payments; equity cash flow instead reflects debt-related cash claims and borrowing.
You, even in a service business, if you bill clients 'Net 30' but pay your contractors 'Net 15', you have a 15-day funding gap. Reducing that gap is a direct cash injection into your venture.
Learning objective
Reconcile operating earnings to cash and quantify working-capital levers.
Understand the mechanism
Specify the FCF definition before comparing companies. Operating cash flow minus capex is a common levered measure; enterprise valuation often uses unlevered FCF. Maintenance and growth capex serve different purposes but can both consume cash.
The cash conversion cycle combines inventory days, receivable days and payable days. Use consistent period lengths and denominators: receivable days generally relate to sales, inventory and payable days to cost of sales. Negative cycles can be favorable but may depend on supplier power and customer prepayment.
Put it to work
Translate days into dollars using an appropriate daily flow. Separate one-time working-capital releases from recurring operating improvement. Shortening collections cannot release the same cash again every year.
Do not improve cash by creating worse economics: pushing suppliers beyond agreed terms can disrupt quality or delivery. Stress customer defaults, inventory obsolescence and seasonal peaks.
Worked example
- 1
Annual credit sales are $3.65m, or $10k per day on a 365-day convention.
- 2
Reducing DSO from 45 to 35 days can release roughly $100k if sales and collection quality stay comparable.
- 3
DIO 30 + DSO 35 − DPO 25 gives a 40-day cash conversion cycle.
Cash efficiency creates flexibility, but a release is not the same as recurring profit.
Your practice lab
Operating cash flow is $2m, capex $0.6m. DIO 50, DSO 40, DPO 30. Compute FCF under OCF-minus-capex and the cycle.
Personal scratchpad · not graded or saved
Case Study: The Dell 'Cash Machine'
In the late 1990s and early 2000s, Dell Inc. perfected a business model that served as a masterclass in working capital management. By selling custom-built computers directly to consumers online, Dell collected cash from its customers almost immediately, resulting in a very low Days Sales Outstanding (DSO).
Simultaneously, Dell's build-to-order system meant it held minimal inventory (low Days Inventory Outstanding, DIO). It also leveraged its massive scale and purchasing power to negotiate favorable payment terms with its component suppliers, extending its Days Payables Outstanding (DPO).
The result was a consistently negative cash conversion cycle. Dell was effectively paid by its customers weeks or even months before it had to pay its own suppliers. This structure generated enormous amounts of free cash flow, which the company could use to fund rapid growth, R&D, and shareholder returns, all without relying heavily on outside capital.
Optimizing the cash conversion cycle, particularly by achieving a negative cycle, can turn a company's operations into a self-funding engine for growth.
Illustrative example — names and figures are composites for teaching.
Estimate the target Cash Conversion Cycle (CCC) for your venture. Break down your target for DIO, DSO, and DPO. Justify why these targets are realistic for your industry and identify the biggest risk to your CCC.
Example: For my consulting firm, the target CCC is 15 days. Target DIO is 0 (no inventory). Target DSO is 45 days, reflecting industry-standard client payment terms. Target DPO is 30 days for contractors and software. The biggest risk is a large client delaying payment, which would dramatically extend DSO and require me to fund operations from cash reserves.
Go deeper — outside resources
- Investor.gov (SEC) — learning hub · Investor.gov (SEC)
Key ideas
- FCF funds all capital allocation
- Working capital is a cash engine
- EBITDA is a shorthand, not cash
Try it: Compute the cash conversion cycle for a public company from its latest 10-K.
Quick check
1. Free cash flow is operating cash flow minus…
2. A shorter cash conversion cycle means…
3. A company successfully negotiates to extend its payment terms with suppliers from 30 days to 45 days. What is a potential negative consequence of this action?
4. For the purposes of enterprise valuation, why is Free Cash Flow (FCF) generally considered a more rigorous metric than EBITDA?
5. A company with $36.5 million in annual revenue successfully reduces its Days Sales Outstanding (DSO) from 60 days to 50 days. What is the approximate one-time cash release from this improvement?
6. A company reports a negative Cash Conversion Cycle. What does this typically imply?