How to Build a Working Capital Schedule

A working capital schedule forecasts the operating assets and liabilities that tie up or release cash: receivables, inventory, and payables. You drive each off a days assumption like DSO, DIO, or DPO, compute net working capital, and flow the period over period change into the cash flow statement. The sign matters: an increase in net working capital consumes cash, so it enters cash flow as a negative.

What working capital is and how it affects cash

Net working capital is current operating assets minus current operating liabilities, typically accounts receivable plus inventory minus accounts payable. It measures how much cash is locked up in running the business between paying suppliers and collecting from customers.

Working capital matters to a model because growth usually consumes cash. As revenue rises, receivables and inventory grow, tying up more cash before it is collected. The cash flow statement captures this through the change in net working capital, not the level, because cash moves only when the balance changes.

Build the schedule with days-based drivers

The cleanest drivers are days ratios. DSO converts revenue into receivables, DIO converts cost of goods sold into inventory, and DPO converts cost of goods sold into payables. This small layout shows one period.

1. Forecast accounts receivable: =DSO / 365 * revenue.
2. Forecast inventory: =DIO / 365 * cost_of_goods_sold.
3. Forecast accounts payable: =DPO / 365 * cost_of_goods_sold.
4. Compute net working capital: =receivables + inventory - payables.
5. Calculate the change: =current_NWC - prior_NWC.
6. Flow the change into the cash flow statement with a negative sign so an increase is a use of cash.

Only the change in net working capital hits cash flow. A positive change of 20 is a 20 use of cash.

The formulas and the sign convention

The sign convention trips up most builders. An increase in an operating asset, such as receivables, uses cash because you have sold but not yet collected. An increase in an operating liability, such as payables, is a source of cash because you have received goods but not yet paid.

The simplest robust approach is to compute net working capital, take its change, and subtract that change in the operating section of the cash flow statement.

• DSO to receivables: =DSO / 365 * revenue.
• DIO to inventory: =DIO / 365 * cost_of_goods_sold.
• DPO to payables: =DPO / 365 * cost_of_goods_sold.
• Net working capital: =accounts_receivable + inventory - accounts_payable.
• Cash flow impact: =-(current_NWC - prior_NWC), so a rising NWC reduces cash.

Pitfalls and what reviewers check

The biggest pitfall is the sign of the change in net working capital on the cash flow statement. If you add the increase instead of subtracting it, operating cash flow is overstated by twice the change. Build a quick check: an investing or financing item should never absorb a working capital movement.

Reviewers also confirm the days drivers reference the right base, revenue for receivables and cost of goods sold for inventory and payables, and that the first forecast period reconciles to the last actual period so there is no spurious one time swing.

Avoid mixing levels and changes. The balance sheet holds the level of each account, while the cash flow statement holds only the change. Keep them clearly separated so the link is auditable.