A 13-week cash flow forecast looks one quarter ahead, week by week, and shows whether you will have enough money to cover what is coming. Thirteen weeks is long enough to act on a problem and short enough to be reasonably accurate.
The basic layout
| Week | 1 | 2 | 3 | … |
|---|---|---|---|---|
| Opening cash | 20,000 | 19,200 | 17,900 | |
| Cash in (customers) | 3,000 | 1,500 | 6,500 | |
| Cash out (suppliers, payroll, rent, tax) | (3,800) | (2,800) | (4,000) | |
| Closing cash | 19,200 | 17,900 | 20,400 |
The closing cash of one week is the opening cash of the next.
How to build it
- Start with today’s cash across your bank accounts.
- Add expected receipts. Take your open invoices and place each in the week you expect it to be paid. Be realistic: use the date a customer usually pays, not just the due date.
- Add known payments. Place each supplier bill in the week you will pay it, then add payroll, rent, loan repayments and tax.
- Add expected new business. Include sales you are confident about, and be cautious.
- Calculate the closing cash each week and look at the lowest point.
What to do with it
If the forecast shows cash dipping below your safety margin, you have weeks to respond rather than days:
- Chase the invoices expected in the weeks around the dip.
- Ask suppliers for later terms or spread a large payment.
- Delay discretionary spending.
- Arrange a short-term facility early, before you need it.
Keep it alive
A forecast is only useful if it is current. Update it weekly: replace last week’s forecast with actuals, add a new week at the end and adjust for what you have learned. Over time you will see how accurate your assumptions are.
Let the software do the heavy lifting
The cash flow forecast in AvrioBooks starts from your cash balance, adds your open invoices and bills week by week, and lets you add your own items such as payroll or rent. It warns you if cash is forecast to run out and shows the week.
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