The 13-week cash flow forecast: why profitable businesses still run out of cash

Many businesses that fail were profitable on paper. They ran out of cash because customers paid late, stock absorbed funds, or a tax payment fell due in the same week as payroll. A 13-week cash flow forecast, which covers one quarter and rolls forward weekly, is the simplest tool for seeing this coming.

How to build it

1. Start with your actual opening bank balance in each currency you hold. Keep USD and ZiG on separate lines.
2. Forecast receipts by week. Use when customers actually pay, not when you invoice. Go customer by customer for your largest debtors.
3. List every payment by week. Include payroll, PAYE, VAT, rent, suppliers, loan repayments, insurance, equipment purchases and quarterly tax payments (QPDs).
4. Calculate the closing balance each week and carry it forward as next week’s opening balance.
5. Flag the weeks where the balance dips below your minimum buffer. These are your decision points.

Keep it simple

A spreadsheet with weeks across the top and receipt and payment categories down the side is enough. Accuracy over the next four weeks matters more than precision in weeks ten to thirteen.

Update it weekly

Replace the forecast with actuals for the week just ended, add a new week 13, and note where you were wrong. Over time this shows you which assumptions, such as customer payment days, you consistently misjudge.

What to do when the forecast shows a gap

• Speed up collections: follow up, offer settlement discounts, or invoice earlier.
• Negotiate supplier terms before you are in difficulty, not after.
• Time discretionary purchases outside tight weeks.
• Arrange short-term funding early. Lenders respond better to a forecast than to an emergency.

For public entities

The same tool works for entities that depend on treasury releases or grants. Mapping expected disbursements against fixed obligations shows how long the entity can operate if funds arrive late.