13-week cash flow forecast template (free Excel)

What a 13-week cash flow forecast is

A 13-week cash flow forecast is a week-by-week projection of the cash a business expects to receive and pay over the next quarter, showing the opening and closing bank balance for each week. It matters because it shows a cash shortfall weeks before it happens, while there is still time to chase customers, move payments or arrange funding.

Thirteen weeks is one quarter: long enough to see the next three monthly payrolls, the next VAT or GST/HST payment and the next loan instalments, and short enough to forecast from real data such as open invoices, committed orders and known payment dates rather than from assumptions. Lenders, turnaround advisers and boards ask for this format because it can be checked week by week against what actually happened.

What is inside the template

The free Excel template has two sheets: How to use, and Forecast. Everything sits on one page so the whole quarter can be read at a glance and printed on one landscape sheet.

Yellow cells are inputs and grey cells are formulas, and the alert row is coloured so the weeks that need action stand out when the sheet is printed for a meeting. The template has no macros, no external links and no passwords, and it works in Excel, LibreOffice Calc and Google Sheets.

• Settings: company, currency, the Monday of week 1, the opening cash balance, a minimum cash balance and any undrawn overdraft or facility.
• Six receipt lines: collections from existing receivables, collections from new sales, VAT refunds, asset sale proceeds, loan drawdowns and other receipts.
• Eleven payment lines: existing payables, new purchases, net salaries, payroll taxes and social security, rent, overheads, VAT, corporate income tax, loan repayments and interest, capital expenditure and other payments.
• For each week: net cash flow, opening cash, closing cash, headroom over the minimum, liquidity including the facility, and an alert of OK, BELOW MINIMUM or OVERDRAWN.
• A summary showing the lowest closing balance and its week, the number of weeks below the minimum, the first breach and an overall status.
• A forecast accuracy block where you enter actual receipts and payments for weeks that have ended and see the variance.

How to build the forecast, step by step

Build the forecast from the most certain cash flows to the least certain. That way, the weeks you can see most clearly are the most reliable, and the assumptions are concentrated where they belong.

• Start from the reconciled bank balance of all accounts at the close of the last working day before week 1.
• Spread existing receivables across the weeks using the ageing report and each customer's actual payment behaviour, not the due date on the invoice.
• Add collections from sales not yet invoiced, lagged by your usual collection period.
• Enter committed payments on their real dates: payroll, payroll taxes, rent, loan instalments, and tax payments from your tax calendar.
• Spread existing payables by due date and by the terms you actually pay on, then add new purchases and overheads.
• Add capital expenditure, asset sales and financing only when they are approved or contracted.
• Set the minimum cash balance, read the alert row and decide what to do about every week that is not OK.

The worked example

The example is a fictional trading company in EUR whose forecast starts on Monday 7 September 2026 with 85,000 in the bank, a minimum cash balance of 40,000 and an undrawn overdraft facility of 25,000. Over the 13 weeks it expects receipts of 356,850 and payments of 354,700, so the forecast closes week 13 at 87,150, which is 85,000 plus 356,850 minus 354,700.

The quarter is not smooth. Week 6 carries a quarterly VAT payment of 18,500, payroll taxes of 11,000 and a loan instalment of 3,200, and closes at 48,150. Week 7 then pays net salaries of 28,000, and although it collects 29,000, it closes at 37,350, which is 2,650 below the minimum. The summary reports one week below the minimum, week 7, and the status reads BELOW MINIMUM IN AT LEAST ONE WEEK. The bank balance never goes negative and liquidity including the undrawn facility is still 62,350 that week, but the business would be eating into the buffer it set for itself, which is exactly the kind of week the forecast exists to catch.

Knowing this in early September gives the company options: collect one or two large invoices earlier, move a discretionary payment such as the week 5 van purchase of 22,000 to a later week, or agree with the bank that the overdraft may be used. The forecast recovers from week 8 as collections from new sales build up.

The logic behind the numbers

The forecast is on a cash basis, which is why it looks different from a profit forecast. Receipts and payments include VAT, because VAT is cash in and out of the bank. Depreciation, accruals and provisions do not appear, because they are not cash. Loan principal and capital expenditure do appear, because they are cash even though they are not expenses. Our guide on why cash flow is not profit explains the differences in more detail.

The mechanics are simple and deliberately rigid. Each week's closing cash is its opening cash plus total receipts minus total payments, and each week's opening cash is the previous week's closing cash. Headroom is closing cash minus the minimum; available liquidity is closing cash plus the undrawn facility. A check at the bottom confirms that week 13's closing balance equals the opening balance plus total receipts minus total payments for the quarter.

Every formula was recalculated by two independent spreadsheet engines and compared with a separate calculation for the example and for two scenarios: an opening balance of 150,000, where every week is OK, and an opening balance of 5,000, where several weeks are overdrawn and the status reads OVERDRAWN IN AT LEAST ONE WEEK.

Rolling the forecast forward each week

A 13-week forecast is a rolling forecast. Every week, on the same day, enter the actual receipts and payments for the week that has just ended, look at the variances, then drop that week and add a new week 13, so the forecast always looks a full quarter ahead. The simplest way is to save a copy of the file, move the week 1 date on by seven days, set the opening balance to the actual bank balance, and shift the remaining weeks one column to the left.

In the example, actual receipts in week 1 were 23,400 against a forecast of 24,000, a variance of 600, and actual payments in week 2 were 27,900 against 28,500. Small variances like these are normal. What matters is whether they are random or always in the same direction: receipts that are consistently late mean the collection assumptions are too optimistic, and every later week of the forecast is too high as well.

Setting the minimum cash balance

The minimum cash balance is the lowest balance management is willing to see in the bank at the end of a week. It should cover the gap between receipts and payments within a week, since a weekly forecast hides the day on which payroll leaves before customers pay, plus a buffer for forecast error. Many businesses start with roughly one month of fixed costs or one payroll cycle and adjust it once they know how accurate their forecast is.

If you have loan covenants that require a minimum liquidity level, set the template's minimum at or above the covenant level so the alert warns you before a breach. Keep the undrawn facility separate, as the template does: a forecast that only works by using the overdraft every month is telling you the business needs more permanent funding.

Review the minimum at least once a year and whenever the business changes shape, for example after opening a new branch, adding a large customer on long payment terms or taking on a new loan with different covenants.

Common mistakes in 13-week forecasts

Short-term forecasts go wrong in predictable ways, and almost all of them make the cash position look better than it is.

• Forecasting receipts on invoice due dates when customers actually pay later.
• Starting from the ledger balance instead of the reconciled bank balance.
• Forgetting quarterly and annual payments: VAT, corporate tax instalments, insurance, annual software licences.
• Leaving out loan principal and capital expenditure because they are not in the profit forecast.
• Treating a budget as a forecast, so the weeks show the plan rather than the cash that is really coming in.
• Never comparing forecast with actual, so the same optimistic assumptions repeat every week.
• Netting receipts and payments into one line, which hides the size of the flows that could go wrong.

When a 13-week forecast is essential

Every business benefits from a short-term cash forecast, but some situations make it essential: rapid growth, when receivables and inventory absorb cash faster than profit generates it; seasonal trading with a known trough; a large capital project; a lost major customer; covenant pressure or a refinancing; and any restructuring, where lenders and insolvency practitioners will expect one. In those situations, update the forecast weekly without exception and share it with whoever provides your funding before they ask for it.

A forecast shared early builds credibility. A lender who sees a well-built 13-week forecast showing a temporary dip in week 7, with the actions already planned, reacts very differently from one who first hears about the problem when the overdraft limit is exceeded. Keep each week's version, because the history of forecasts against actuals is the evidence that your numbers can be trusted.

Doing this in Skyline Nexus ERP

Skyline Nexus ERP supplies the data a 13-week forecast is built from. The AR Aging Report and AP Aging Report in the Fiscal Authority reports split open balances into current, 1-30, 31-60, 61-90 and over 90 days, per customer and supplier, which is the starting point for the receivables and payables lines. The Customer Financial Centre and Supplier Financial Centre add customer and supplier ledgers and statements of account, which show how each counterparty actually pays.

In the Treasury module, the Daily Cash Position and Bank Balance Summary reports give the opening balance, Payment Processing lists Scheduled Payments, and PDC Management tracks post-dated cheques received and issued, which are future cash flows with known dates. Bank Reconciliation makes sure the opening balance you forecast from is reconciled. The forecast itself stays in the spreadsheet, where you control the assumptions; Skyline Nexus ERP keeps the numbers going into it current.