13-Week Cash Flow Forecast: The Complete Guide for Growing Businesses

A 13-week cash flow forecast is a rolling, week-by-week projection of expected cash receipts and payments over the next quarter. It tracks money actually moving in and out of bank accounts, not revenue or profit on an accruals basis.

This distinction matters: a profitable business can still run out of cash, and a loss-making one can sit on a strong balance. The 13-week forecast is the tool that separates the two.

Most professional cash forecasts use the direct method, building the number from the bottom up by listing each category of inflow and outflow. It is more transparent, easier to audit, and more useful for operational decisions than the indirect method, which adjusts net profit for non-cash items and is better suited to annual reporting.

Cash Inflows

• Customer receipts from trade receivables, scheduled against realistic debtor days
• Advance payments, deposits, and milestone billings
• Loan drawdowns, equity injections, and shareholder contributions
• Asset sale proceeds, grants, and tax refunds

Cash Outflows

• Supplier payments, phased against actual payment runs and terms
• Payroll, social security, and employer contributions
• VAT, corporate income tax, and withholding tax
• Rent, utilities, insurance, and recurring overheads
• Debt service: interest, amortisation, and fees
• Capital expenditure and committed project spend
• Intercompany transfers within a group structure

Sample data for illustration only. Numbers represent a typical European scaleup, not actual client figures.

A usable model has one column per week, one row per cash flow category, and a clear opening and closing balance per period. The closing balance of one week is the opening balance of the next.

scroll for all 13 weeks →

Each row should tie back to a source. Receivables roll off the aged debtor list. Payables come from the aged creditor list plus confirmed purchase orders. Payroll is driven from the headcount file. Tax is driven from the filing calendar. The forecast is only as good as the discipline behind these inputs.

1. 1

   1.Pull the opening cash position

   Take the closing balance from the bank, not the ledger, and split it by entity and currency if the group is multi-entity. Operating accounts, payroll reserves, and restricted or covenant accounts should be reported separately so that free cash is visible at a glance.

2. 2

   2.Schedule confirmed inflows

   Start with invoices already raised. Assign an expected pay date based on your actual debtor days, not invoice terms. Layer in confirmed financing drawdowns and any one-off receipts such as tax refunds or grant payments.

3. 3

   3.Schedule known outflows

   Load approved purchase orders, recurring overheads, payroll dates, debt service dates, and the tax calendar. Tax payments are a common source of nasty surprises, add them the day a return is filed, not the day payment falls due.

4. 4

   4.Layer in forecast inflows for weeks 4–13

   Use pipeline conversion rates and historical seasonality, not the sales team's best case. A single base case is sufficient for weekly cadence. A downside case, typically a 10–20% haircut on pipeline and a 10–15 day stretch on debtor days, is useful for board and lender reporting.

5. 5

   5.Build in covenant headroom

   For any business with a leverage, liquidity, or minimum cash covenant, the forecast should show headroom on a weekly basis, not just at test dates. This is where the 13-week view earns its place in the board pack.

6. 6

   6.Update weekly, replacing forecast with actuals

   Every Monday, replace the prior week's forecast with actual figures, extend the horizon by one week, and review the variance. The value is in the cadence. A forecast updated monthly is a reporting exercise. A forecast updated weekly is a management tool.

Every business benefits from rolling cash visibility. The cost of not having it rises sharply in certain situations:

• Rapid growth — working capital is absorbing cash faster than profit is generating it
• Lender and investor reporting — covenant headroom must be demonstrable, not asserted
• Restructuring or refinancing — any period of financial stress demands daily clarity
• Post-acquisition integration — two sets of assumptions need reconciling into one view
• Seasonal businesses — the gap between peak collections and trough payables can be wide and brutal
• Multi-entity groups — cash sits across banks, currencies, and jurisdictions simultaneously