The components of working capital
The three core components of operating working capital are: Accounts receivable (AR) — money owed to the company by customers who have been invoiced but not yet paid. This is cash the company has earned but not yet received. Inventory — goods purchased or manufactured but not yet sold. This is cash tied up in products waiting to generate revenue. Accounts payable (AP) — money the company owes to suppliers it has received goods or services from but not yet paid. This is essentially interest-free credit from suppliers that delays cash outflow. Working capital = AR + Inventory − AP. The goal of working capital management is to minimise cash tied up in AR and inventory while maximising AP (paying suppliers as late as contractually allowed).
Why working capital management matters
Amazon famously has negative working capital: it collects cash from customers the moment they order, holds inventory for only a few days, and pays suppliers on 30-60 day terms. This means Amazon is essentially funded by its suppliers and customers rather than its own capital — a structural competitive advantage. Retail banks have extreme negative working capital because deposits (which customers can withdraw) fund long-term loans. At the other extreme, a construction company that invoices at project completion but buys materials upfront may have very high positive working capital — tying up significant capital in receivables and materials for months at a time. Managing the cash conversion cycle (days of inventory + days of receivables − days of payables) is how finance teams optimise the capital tied up in operations.
“More businesses fail for lack of cash than for lack of profit. A company can be profitable and still go bankrupt if it cannot collect its receivables fast enough to pay its creditors.”
What this means for you
When evaluating companies, working capital analysis reveals operational efficiency. Companies with deteriorating days-sales-outstanding (customers taking longer to pay) or rising inventory days may be facing demand weakness or operational problems before it shows in profit figures. Companies with negative working capital and strong brands (like consumer staples companies) have a structural funding advantage. For anyone running a small business, working capital management is often the difference between survival and failure — invoice quickly, chase receivables diligently, and negotiate supplier payment terms to maximise the cash in your account at all times.