Working Capital on the Cash Flow Statement

Introduction

In its fiscal year ended January 2025, Walmart built up its inventory, and on its own that build would have absorbed $2.8 billion of operating cash. But growth in Walmart's accounts payable provided $3.2 billion over the same period, so its suppliers more than funded the extra stock, and working capital as a whole added a little cash to the year. Two lines on the cash flow statement, one negative and one positive, tell that story.

Working capital is where accrual accounting and cash part ways most visibly in the operating section. Revenue is recorded before customers pay; inventory is bought before it is sold; costs are recorded before suppliers and employees are paid; customers sometimes pay before they receive anything. Each timing gap leaves a balance on the balance sheet, and each change in those balances moves operating cash flow. The rule that governs the signs is simple, but applying it correctly to every balance, and reading what the changes say about a business, is a skill bankers use constantly. Working capital is the third and most variable part of the reconciliation described in cash flow from operations: the indirect method, after non-cash charges and gains.

The rule follows from the balance sheet. If an operating asset rises, the company has put cash into it, or has recorded revenue it has not yet collected, so operating cash flow is lower than net income. If an operating liability rises, the company has recorded a cost it has not yet paid, or has collected cash it has not yet earned, so operating cash flow is higher than net income. Decreases work in reverse.

Operating working capital

The current assets and liabilities that arise from day-to-day operations, typically receivables, inventory and prepaid expenses less payables, accrued liabilities and deferred revenue. Cash, short-term debt and other financing items are excluded. Changes in it appear in the operating section of the cash flow statement.

The effect of each balance can be summarized in one table:

Why the Rule Works: A Balance Sheet Proof

The rule can be derived directly from the accounting equation. Split assets into cash and everything else: cash equals liabilities plus equity minus non-cash assets. The same relationship holds for changes over a period:

The change in equity is driven mainly by net income, which is why the indirect method starts there. Every increase in a non-cash asset enters with a minus sign, and every increase in a liability with a plus sign. The working capital lines on the cash flow statement are simply this identity applied to the operating balances, which is also why a model whose working capital signs are wrong will not balance. The identity itself is explained in the accounting equation.

Following a transaction through all three statements shows why the signs work. Each case below changes one working capital balance, and in each the income statement, the cash flow statement and the balance sheet tell the same story from different angles: what was earned or incurred, what cash moved, and what was left owing or owed.

Receivables: Revenue Before Cash

Start with a sale on credit: a company sells goods for $100, payable in thirty days, that cost $60 and came from inventory. Ignoring tax for simplicity:

Net income rises by $40, but no cash has moved. The cash flow statement removes the $100 of revenue not yet collected by subtracting the increase in receivables, and adds back the $60 of inventory consumed, whose cash left when the goods were bought. When the customer pays next period, receivables fall by $100 and operating cash flow rises by the same amount, with no effect on that period's net income.

Inventory and Payables: Stock Before Payment

Buying inventory on credit shows the liability side. If the company buys $80 of new stock from a supplier on sixty-day terms, nothing reaches the income statement, because the goods have not been sold:

The inventory increase uses cash and the payables increase provides it, netting to zero, which matches reality: the company has the goods but has not paid. If the company had paid cash instead, only the inventory line would appear and cash would fall by $80. That is why the balance between inventory and payables growth, as in Walmart's case, decides whether stocking up costs cash.

Deferred Revenue: Cash Before Revenue

Deferred revenue works the other way round. A software customer prepays $50 for a year of service that has not yet started:

Cash rises immediately, but revenue will be recognized only as the service is delivered, so the increase in deferred revenue appears as a source of cash in operating activities. As the service is delivered, revenue rises and deferred revenue falls, with no further cash. Subscription businesses that grow their billings therefore often show operating cash flow above net income, a pattern covered in deferred revenue on the three statements.

Accruals and Prepaids: Expense and Payment Out of Step

Accrued expenses follow the same logic as payables. If employees earn $30 of wages in the last week of the year, paid in the first week of the next, net income falls by $30, accrued liabilities rise by $30, and operating cash flow is unchanged, because the add-back of the accrual offsets the expense. Prepaid expenses mirror accruals: paying $24 in advance for a year of insurance reduces cash immediately and creates a prepaid asset, so the increase in prepaid expenses is subtracted, and as the coverage is used up the expense is recognized while the prepaid balance falls and is added back. In both cases the cash flow statement realigns the period's costs with the period's payments. The more general method for tracing any transaction is set out in tracing a transaction through the statements.

Walmart's cash flow statement shows how the working capital lines can swing from year to year for the same business:

Each year tells a different story. In fiscal 2024, the inventory line released $2.0 billion and the payables line provided $2.5 billion, a double benefit that followed the industry's inventory glut of 2022, when retailers were left holding excess stock as consumer spending shifted. In fiscal 2025, rebuilding inventory used $2.8 billion, but payables provided $3.2 billion, so suppliers financed the build. Across the three years, working capital added cash in every year, a typical pattern for a large retailer that collects from shoppers at the till and pays suppliers on credit. These lines are not simply the change in each balance sheet figure: inventory on Walmart's balance sheet rose only about $1.5 billion in fiscal 2025, because the company states the lines net of acquisitions and dispositions, and currency movements on foreign subsidiaries' balances never pass through them.

The accrued liabilities line shows a different kind of swing. In fiscal 2023 it added $4.4 billion, and in fiscal 2024 it took back $1.3 billion. Much of that movement was a single item: Walmart accrued about $3.3 billion for opioid litigation settlements in fiscal 2023 and, as its fiscal 2024 Form 10-K reports, paid almost all of it in fiscal 2024. A year in which accruals build sharply flatters operating cash flow, and the year in which they are paid reverses part of the benefit. Reading two or three years together avoids mistaking such timing for a change in the business.

For most businesses, working capital grows with sales, so growth itself becomes a use of cash. If customers take a month to pay and inventory sits for two months, every additional dollar of annual sales ties up more cash in receivables and stock, partly offset by payables. The net time cash is tied up is measured by the cash conversion cycle: days of inventory plus days of receivables, less days of payables. How each component is measured and forecast is explained in working capital drivers.

A simple example shows the arithmetic. A company with $1,200 million of annual sales whose operating working capital equals 45 days of sales holds about $148 million of it. If sales grow by 20% to $1,440 million with the same 45 days, it needs about $178 million, so growth absorbs about $30 million of cash that year, all of it subtracted in operating cash flow even though profits are rising. A business growing fast with a long cycle can report record earnings and shrinking cash, the problem explored in why profitable companies run out of cash.

One Day Is Worth Real Money

The same arithmetic gives a useful rule of thumb. Each day of receivables ties up one day of sales, so for the company with $1,200 million of annual sales, one day is worth about $3.3 million of cash, and collecting from customers five days faster releases about $16 million. Inventory and payable days are measured against cost of goods sold instead, so if that cost is $900 million, letting inventory build by ten days absorbs about $25 million. Management teams that set working capital targets in days, and buyers that model operational improvements after an acquisition, think in exactly these terms.

Cash conversion cycle

The number of days between paying for inventory and collecting cash from customers, calculated as days inventory outstanding plus days sales outstanding minus days payable outstanding. A longer cycle means more cash tied up in operations for each dollar of sales; a negative cycle means customers and suppliers fund the business.

Businesses with a negative cycle work the other way. Amazon collects from customers well before it pays its suppliers, so as it grows, working capital provides cash rather than absorbing it. Subscription software companies reach a similar result by a different route: customers who prepay annual contracts fund the business through deferred revenue, a balance the cycle formula leaves out. Both can fund much of their growth from customers and suppliers rather than from their own balance sheets.

Working capital changes are easy to read mechanically and easy to misread analytically. Several distortions recur:

The financing point deserves the most attention, because it can make operating cash flow look structurally better than it is. A company that starts selling its receivables to a factor collects cash weeks earlier, and reports the acceleration as a working capital release in operating activities, while a company that lengthens payment terms through a supplier finance program shifts part of its funding to a bank without any change in its stated debt. The accounting and the adjustments bankers make are covered in supplier finance and factoring. The size of the effect is easy to estimate: a company with $1,200 million of annual sales that sells its receivables thirty days earlier than customers would pay releases about a month of sales, roughly $100 million, in the year it starts the program, and nothing extra afterwards. Adding the factored receivables back to working capital, and treating the arrangement like borrowing, gives a fairer comparison with peers that collect on normal terms.

Valuation

In valuation, projected changes in working capital reduce or add to free cash flow in a discounted cash flow model, a link covered in the Valuation guide's article on the three-statement model. A company expected to grow quickly with a positive cash conversion cycle has lower free cash flow than its earnings suggest, and the difference is permanent for as long as the growth continues. Many models express working capital as a percentage of revenue rather than in days, which is quicker but hides which balance is driving the change; for the terminal year of a discounted cash flow, the working capital investment should match the long-term growth rate, so a business growing 3% a year keeps investing about 3% of its working capital base annually.

The Working Capital Peg in a Sale

In a sale, the purchase agreement defines net working capital for the deal, usually excluding cash, debt and income taxes, and sets a target level, the peg, usually based on a trailing average to smooth seasonality. At closing, the working capital actually delivered is compared with the peg and the price adjusts dollar for dollar. If the peg is $150 million and the business delivers $140 million, the buyer pays $10 million less. The mechanism exists precisely so that a seller cannot release working capital just before the sale and keep the cash, and testing the peg is a core part of a quality of earnings review.

Disputes over the closing adjustment are common, and they usually turn on accounting policies rather than arithmetic: whether the closing balance sheet applies the same inventory reserves, accrual estimates and cutoff rules as the historical periods used to set the peg. Purchase agreements therefore specify the policies to be applied, and the consistency of those policies matters as much as the balances themselves.

Lending Against Working Capital

Lenders use working capital directly too. Asset-based loans advance a percentage of eligible receivables and inventory, so the borrowing capacity of a distributor or retailer rises and falls with its working capital, and seasonal businesses draw on revolving credit facilities to fund the build before their peak season and repay it afterwards. For these borrowers, the working capital lines on the cash flow statement are effectively the explanation of their debt balance.

The sign rule takes a minute to learn and a career to apply well. Read balance by balance, the working capital lines show how a company is financed by its customers and suppliers, how much cash its growth requires, and whether a year's operating cash flow reflects the business or a timing effect that will not repeat.