About This Template
The 13-week cash flow forecast is widely regarded as the gold standard tool for short-term liquidity management. Unlike a P&L forecast, which shows accounting profit, or an annual budget, which operates at too high a level of aggregation, the 13-week model tracks actual cash receipts and payments week by week — giving you and your board a precise, real-time view of where the cash balance is heading over the next quarter.
This template was built for growth-stage companies that need to move beyond spreadsheet-in-a-drawer cash management. It is particularly relevant for any company with less than 18 months of runway, any regulated firm (such as an EMI or payment institution) that must demonstrate treasury controls to the FCA, and any company that has entered or is approaching a fundraising process where investors will expect a credible near-term cash forecast as part of diligence. It is equally useful for companies going through a period of rapid hiring or significant capital expenditure where the monthly budget is not granular enough to catch cash timing issues.
The template contains seven sheets structured to institutional standards: a Cover sheet with model metadata and version control, an Instructions sheet with a colour-coding legend and step-by-step guide, a clickable Index for navigation, the Forecast sheet for weekly cash flow planning, a Variance sheet for comparing actuals against forecast, a Checks tab with automated reconciliation controls, and an Executive Dashboard summarising KPIs and the 13-week cash flow trajectory. The design is intentionally clean — no macros, no VBA, no protected ranges — so your team can adapt it without specialist knowledge.
What's Included
- Cover sheet — Model documentation, version control, confidentiality notice, model purpose and scope, tab structure guide, and key assumptions
- Instructions sheet — Colour-coding convention (blue = inputs, black = formulas, green = cross-sheet links, grey = inactive, red = errors), ten-step usage guide, navigation map, and calculation settings
- Index sheet — Clickable table of contents with hyperlinks to each worksheet, grouped by Documentation, Inputs & Calculations, Tracking, Controls, and Outputs
- Forecast sheet — 13 weekly columns with receipt categories (Sales, Contract, Other ×2), payment categories (Payroll & NI, Rent, Suppliers, HMRC/VAT, Software, Marketing, CapEx, Other ×2), net cash flow calculation, rolling opening/closing balance, minimum buffer, and surplus/(shortfall) indicator. All inputs in blue; all calculations in black formulas
- Variance sheet — Forecast vs Actual vs Variance columns for all 13 weeks. Forecast columns link directly to the Forecast sheet; Actual columns are manual entry from bank statements
- Checks sheet — Seven automated reconciliation controls: cash flow continuity, Total Receipts integrity, Total Payments integrity, opening balance carry-forward, Net CF consistency, Variance sheet linkage, and Total column integrity. All checks display PASS/FAIL with a global model status indicator
- Dashboard sheet — Executive KPI summary (Total Receipts, Total Payments, Net Cash Flow, Opening and Closing Balance, Minimum Buffer, Weeks Below Buffer, Model Status) plus a week-by-week summary table ready for board distribution
How to Use This Template
- Set your opening cash balance. On the Forecast sheet, enter your current bank balance (or your projected balance at the start of the forecast period) in the Opening Balance input cell. This is the single most important input — get it from your bank statements, not your accounting system, to avoid timing differences.
- Enter your minimum cash buffer. Input the minimum cash balance you want to maintain at all times. For most growth-stage companies this should be at least one month of gross burn. This figure feeds the Surplus/(Shortfall) row and will highlight red when any week is projected to fall below it.
- Fill in the week start dates. Enter the Monday date for each of the 13 weeks in Row 7 of the Forecast sheet. This keeps the model anchored to your actual calendar and makes it easier to align payment dates to specific weeks.
- Enter weekly receipts by category. For each week, input expected cash receipts in the relevant rows: Sales receipts (direct card/bank receipts from customers), Contract income (milestone payments, project-based billing), and up to two additional Other income rows. Remember: this is cash received, not invoiced. Adjust for your typical collection lag — if customers pay on 30-day terms, a January invoice arrives as February cash.
- Input your payment schedule. Go through your payment run calendar and fill in each category week by week. Payroll and NI should align to your pay dates. Rent typically falls on the first of each quarter. Supplier payments should match your payment run dates. HMRC/VAT should align to your VAT return submission and payment dates. Be specific: this is the key exercise that reveals timing crunches invisible in a monthly model.
- Review the Net Cash Flow and Closing Balance rows. The model automatically calculates Total Receipts, Total Payments, Net Cash Flow, and the Closing Balance (which becomes the next week's Opening Balance). Scan these rows first. Any week where the Closing Balance dips below your minimum buffer will be flagged in the Surplus/(Shortfall) row.
- Identify and address shortfall weeks. If any weeks show a shortfall, work backwards: can a payment be deferred by one week? Can a receipt be accelerated by issuing an invoice earlier or chasing a slow-paying customer? Can you draw on a credit facility for that specific period? The 13-week model makes these conversations actionable and specific rather than abstract.
- Update the Variance sheet each week. As each week closes, enter the actual receipts and payments in the Actual columns of the Variance sheet. The Variance column will automatically calculate the difference. Review significant variances — a consistent pattern of receipts arriving one week later than forecast suggests your collection lag assumption needs adjusting.
- Roll the model forward each week. At the end of each week, move the forecast forward by one week: delete the oldest week, add a new Week 13 with fresh estimates, and carry forward the actual closing balance as the new opening balance. This keeps the model permanently 13 weeks forward-looking.
- Customise the category labels. The receipt and payment row labels are text cells — rename them to match your specific business. If you don't have rent, rename that row to 'Office costs'. If you have a specific large supplier that dominates your payments, give them their own named row. The more specific the labels, the more useful the model becomes as an operational tool.
- Review the Checks tab before distributing. All seven automated reconciliation checks must show PASS before sharing the model with your board or investors. If any show FAIL, review the flagged formula or input — the check descriptions on the tab explain exactly what each control is testing. A clean Checks tab is your audit trail.
- Use the Dashboard for board distribution. The Dashboard sheet pulls KPIs directly from the Forecast sheet and produces a one-page executive summary suitable for board packs and investor diligence. Share the Dashboard with stakeholders who do not need to see the full weekly detail — it presents the 13-week picture in a clean, presentation-ready format.
Frequently Asked Questions
What's the difference between a 13-week cash flow forecast and a P&L forecast?
A P&L forecast shows accounting revenues and expenses, which are recognised when earned or incurred regardless of when cash moves. A 13-week cash flow forecast tracks only actual cash received and paid. The difference matters enormously in practice: a business with strong invoice-based revenue but slow-paying customers can show healthy P&L profit while simultaneously running out of cash. The 13-week model eliminates this blind spot by focusing entirely on when money actually lands in or leaves your bank account.
How often should I update the forecast?
Weekly is the standard cadence. The model should be updated every Monday morning with the previous week's actuals, and the 13-week horizon should roll forward by one week. For companies in a cash-tight position (under 12 weeks of runway) or those in active fundraising, a twice-weekly refresh is not unreasonable. The forecast loses much of its value if it is only updated monthly — by then, any timing crunch it might have flagged has already arrived.
What do I do when a week shows a shortfall?
A projected shortfall means your forecast closing balance that week will fall below your minimum buffer. The immediate response options are: (1) accelerate a receipt — contact customers with outstanding invoices and request payment by the end of that week; (2) defer a payment — negotiate a one-week extension with a supplier or delay a discretionary payment; (3) draw on a revolving credit facility if you have one; or (4) if none of these are sufficient, escalate to the board immediately. The value of the 13-week model is that it gives you 3–13 weeks of lead time to address a problem rather than discovering it on the day your payment run bounces.
How does collection lag affect my receipts inputs?
Collection lag is the average number of days between issuing an invoice and receiving cash. If your collection lag is 35 days, a Monday payment run generates cash approximately five weeks later. To model this correctly, your receipts in any given week should be based on invoices issued roughly five weeks earlier, not invoices issued that week. Track your actual collection lag as a KPI — it tends to deteriorate as companies scale and sales teams prioritise new logos over chasing outstanding invoices. Rising collection lag is one of the earliest warning signals of a cash crunch.
Should I include VAT in my payment amounts?
Yes. The cash flow forecast should always use gross cash amounts — i.e., the full amount that will physically leave your bank account, including VAT. Your accounting system records transactions net of VAT, but your cash flow model must reflect actual cash flows. This means the HMRC/VAT row should include your net VAT payment (output VAT collected minus input VAT reclaimed) due on your quarterly return date. Including VAT is especially important for companies with significant CapEx or marketing spend where input VAT reclaims are material.
Can I extend this template to 26 weeks?
Yes, and for some businesses a 26-week horizon is more appropriate — particularly for companies with quarterly billing cycles or large seasonal payment obligations. To extend: simply copy the Week 13 column and paste it to the right, updating the week date, and extend the formula ranges in the Total Receipts, Total Payments, and Balance rows. Be aware that forecast accuracy degrades significantly beyond 13 weeks, so weeks 14–26 should be treated as directional estimates rather than precise projections. Consider using monthly blocks (rather than weekly columns) for the outer period and switching to weekly detail only for the first 13 weeks.
