A 4-Week Cash Flow Forecast That Fits on One Page

You know roughly what the shop takes in a week. What catches you out is the week where rent, a quarterly insurance payment, a supplier invoice and wages all land within four days of each other. That week was always going to be tight; you just did not see it coming until the card was declined at the wholesaler. A cash flow forecast is not a financial exercise. It is a warning device that tells you which week is going to be tight, early enough to do something about it. All figures below are made-up examples, so read them in your own currency.

Keep the ambition low. Four weeks ahead, one page, updated on the same morning every week. Anything longer than four weeks in a small shop is guesswork, and anything more detailed than one page stops getting updated by the third week. The forecast does not need to be accurate. It needs to be roughly right and always current, because its only job is to tell you which week goes red.

What you need before you start

• Your real opening balance: what is in the business bank account plus the cash you hold, today.
• The last four weeks of takings, so you have a realistic weekly range rather than an optimistic one.
• Your fixed outgoings and the dates they leave: rent, insurance, subscriptions, finance payments, phone.
• Supplier invoices already due or falling due within the next four weeks, with their dates.
• Any tax or social contribution payment your accountant has told you is coming, even if the amount is approximate.
• Money customers owe you, with an honest view of when it will actually arrive rather than when it was promised.

Start with the opening balance and be strict about it. It is what is in the account this morning plus the float in the till, minus anything in that balance that is not yours to spend: a customer deposit for work not yet done, tips collected on card and owed to staff, tax you are holding. Owners routinely start a forecast from a bank balance that includes several hundred of other people's money, and then the forecast is wrong from line one.

For money coming in, use the last four weeks and take the lower end of the range, not the average. If your weeks ran 1,850, 2,100, 1,640 and 1,970, do not forecast 1,890. Forecast 1,700 and be pleasantly surprised. An optimistic forecast is worse than no forecast, because it lets you commit money you do not have. Then adjust for what you already know: a public holiday, a closed week, a local event, the month when half the neighbourhood goes away.

The four buckets of money going out

• Fixed and dated: rent, insurance, subscriptions and finance payments, which you can enter with real dates because they never move.
• Staff: wages and any related contributions on their normal payment days, including the month that happens to have five paydays.
• Stock and suppliers: what you must order to keep trading, plus invoices already outstanding with their due dates.
• Occasional and forgotten: the annual licence, the equipment service, the accountant's fee, the repair you keep postponing.
• Your own drawings, because a forecast that pretends the owner takes nothing out describes a business you are not running.

The page itself is four columns, one per week, and four rows. Row one is the opening balance. Row two is money in. Row three is money out. Row four is the closing balance, which becomes the next week's opening balance. That is the whole structure. You can build it in a spreadsheet in ten minutes or draw it on paper and keep it in the till drawer. The format matters far less than whether you actually look at row four.

A made-up example. You open week one with 1,240 in the bank, forecast 1,700 in and 1,450 out, and close on 1,490. Week two looks similar and closes on 1,690. Week three is where rent of 900 and a supplier invoice of 620 both fall alongside normal costs, so 2,900 goes out against 1,700 in and you close on 490. Week four has wages of 1,100 on the Friday, and you would close on 60. Nothing here is a disaster, but week four is clearly the pinch and you found it three weeks early, which is enough time to ask the supplier for a fortnight, chase two unpaid invoices, or hold back a stock order.

What the page is telling you

• A closing balance that drops below your comfort level is a warning rather than a crisis, if you spot it two or three weeks out.
• A negative closing balance in week three or four means a decision is needed now, while you still have options.
• A forecast that stays flat while takings are good usually means money is leaking to costs you have stopped noticing.
• A week where money in is unusually high should be treated as the week to clear something down, not the week to spend.
• If every week is tight regardless of takings, the problem is margin rather than timing, and no forecast will fix that.

When a week goes red you have more levers than you think, and every one of them works better with notice. You can ask a supplier for an extra week, which is a normal conversation before the due date and an awkward one after it. You can chase what customers owe you, which is money you have already earned. You can move a non-urgent stock order. You can delay your own drawings. What you should not do is find out on the day and reach for whatever credit is nearest.

Update it on the same morning every week and give it ten minutes. Move each column left, add a new week four, correct the opening balance to what the bank actually says, and adjust anything you now know that you did not know last week. Ten minutes a week buys you roughly three weeks of warning on every cash problem the shop is going to have.