A 13-week cash-flow forecast shows when money is expected to enter and leave the business. Weekly detail makes short-term timing visible without pretending you can predict the entire year precisely.
Begin with available cash
Use the cash actually available at the start of week one. Exclude restricted funds and amounts already committed if they cannot support normal operations.
Forecast inflows by expected payment date
List customer collections in the week you realistically expect to receive them, not the invoice date. Use customer payment history and current conversations. Include other income only when it is reasonably dependable.
Forecast outflows by due date
Include payroll, contractors, rent, software, taxes, loan payments, owner pay, inventory, and planned purchases. Do not spread a quarterly bill evenly if the cash will leave in one week.
Update it every week
- Replace the completed week with actual results.
- Investigate differences between forecast and actual cash.
- Add a new thirteenth week.
- Update assumptions based on new information.
Focus on the lowest projected cash balance. That week tells you when action is needed. Possible actions include accelerating collections, moving a purchase, negotiating vendor timing, reducing discretionary spending, or arranging financing before the need becomes urgent.