How to Build a 13-Week Cash Flow Forecast for Your Agency
Agencies rarely fail because they lack revenue. They get squeezed because cash arrives later than expected while payroll, contractors and software leave on schedule. A 13-week cash flow forecast fixes that by showing, week by week, how much cash you will actually have — roughly a quarter ahead.
Why 13 weeks?
Thirteen weeks is one quarter. It is short enough to be accurate (you know most of your clients, invoices and bills) and long enough to give you time to act: chase an invoice, delay a hire, or push a retainer renewal before a gap turns into a crisis.
The columns you need
| Row | What goes in it |
|---|---|
| Opening cash | Bank balance at the start of the week (last week's closing cash) |
| Client receipts | Payments you expect to land that week, by client |
| Payroll & contractors | Every pay run and contractor payment, on its real date |
| Fixed costs | Rent, software, insurance, loan payments |
| Taxes & one-offs | Quarterly estimates, annual renewals, equipment |
| Closing cash | Opening cash + receipts − all payments |
| Safety floor check | Flag any week where closing cash falls below your minimum buffer |
Step by step
- Start from the bank, not the P&L. Use your real balance today.
- Forecast receipts by payment behavior. If a client on Net-30 historically pays in 50 days, put the cash in week 7, not week 4.
- Load every outflow on its actual date. Annual software renewals and quarterly taxes are the classic surprises.
- Set a safety floor. Decide the minimum cash you never want to drop below and flag weeks under it.
- Roll it weekly. Every week, replace the forecast for the week just ended with actuals and add a new week 13.
Common mistakes
- Using invoice dates instead of expected payment dates.
- Forgetting annual and quarterly costs.
- Counting pipeline deals that are not signed.
- Building it once and never updating it.
Skip the setup: get the ready-made 13-week model
Start with the Agency Cash Forecast ($97) — the 13-week model on its own, with a code that takes $97 off the full Vault later.
Get the Cash Forecast – $97See the full Vault