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The practical view
Start with the cash actually available today. Add customer payments when they are expected to clear, not when invoices are issued. Subtract payroll, rent, taxes, supplier payments, debt service and other outflows on their expected payment dates. Calculate the closing balance for each week and carry it forward. Then create a conservative scenario for delayed receipts or higher costs. Review the forecast weekly, reconcile it with the bank balance and update assumptions as new evidence arrives.
Key takeaways
- Forecast cash by payment date, not accounting recognition date.
- Separate committed amounts from estimates and uncertain opportunities.
- Focus on the forecast low point and the actions available before it arrives.
Choose a useful time horizon
A 13-week forecast is detailed enough for near-term decisions and long enough to expose payroll cycles, tax payments and supplier commitments. A monthly forecast can extend beyond that horizon for planning. Use weekly rows for the period where timing matters most and monthly rows for the period where estimates are less certain.
The forecast should answer a practical question: when is cash tight, why, and what can management do before then? More distant precision does not make a forecast more reliable.
Build the forecast from dated cash movements
Begin with opening cash that is available for operating use. List expected receipts by customer and week. Use the payment behaviour of each customer, not only the invoice due date. Then list payroll, supplier payments, rent, loan payments, tax remittances, subscriptions, capital purchases and owner distributions.
Opening cash + Cash receipts − Cash payments = Closing cashIf opening cash is $40,000, receipts are $27,000 and payments are $34,000, closing cash is $33,000.
Show certainty and scenarios clearly
Label each line as confirmed, expected or conditional. A signed contract is not the same as cash in the bank, and an unsigned proposal should not fund a fixed commitment. Create a base case and a conservative case using slower collections, lower sales or higher costs. The difference between the cases is a useful measure of exposure.
Do not hide financing assumptions. If a line of credit is required to keep the balance positive, show the draw, interest and repayment separately. The forecast should reveal the funding need, not smooth it away.
Turn the forecast into a weekly control
Each week, replace the prior estimate with the actual bank movement, investigate material differences and update future timing. Assign collection actions, payment decisions and spending approvals to named owners. Track whether forecast accuracy is improving.
A forecast is valuable even when it is wrong, provided the variance teaches the team something. Repeatedly late customer payments, underestimated payroll costs or missed subscriptions often point to an operating issue that deserves its own fix.
SOURCES AND FURTHER READING