90-Day Cash Flow Forecast for Small Business
Profit on paper is not cash in the bank. Build a simple 90-day cash flow forecast with a worked example and spot cash gaps before they hit. Try the method.
Profit is not cash
A business can be profitable on paper and still struggle to pay salaries or suppliers. You sell and invoice today, but the money arrives in 30, 60 or 90 days, while rent, payroll and tax bills fall due on fixed dates. A cash flow forecast shows that gap in advance, so you can act before it reaches your bank account.
What you need to build one
You only need three inputs:
1. Cash in: unpaid sales invoices, with the date you realistically expect payment (not just the due date).
2. Cash out: supplier invoices and bills still to pay, with their due dates.
3. Fixed and tax commitments: payroll, rent, loan repayments and tax deadlines such as VAT returns and income tax.
Step by step: a 90-day forecast
Step 1. Start from your real bank balance today. Not the accounting profit, the actual cash.
Step 2. List expected cash in by week or month. Use the date you expect payment, based on how each client actually pays.
Step 3. List cash out in the same periods. Include the items that are easy to forget: VAT, quarterly tax payments, annual insurance and software subscriptions.
Step 4. Calculate the closing balance for each period. Opening balance + cash in - cash out.
Step 5. Look for the lowest point. That is the number that matters, not the total at day 90.
A worked example
A small studio starts with 8,000 in the bank:
| Month 1 | Month 2 | Month 3 | |
|---|---|---|---|
| Opening balance | 8,000 | 3,500 | -2,000 |
| Cash in (client payments) | 6,000 | 4,000 | 16,000 |
| Payroll and rent | -9,000 | -9,000 | -9,000 |
| Supplier bills | -1,500 | -500 | -1,500 |
| VAT payment | 0 | 0 | -3,000 |
| Closing balance | 3,500 | -2,000 | 500 |
On paper the studio may be profitable, yet in month 2 the account goes negative, and it only recovers when a large client payment lands in month 3. Seeing this at day 1 gives time to chase invoices, negotiate supplier terms or arrange a short-term facility, instead of discovering it on payday.
Ways to close a cash gap
Review it every week
A forecast is only useful if it is updated. Once a week, replace expectations with actuals, move payments that slipped and extend the horizon. Ten minutes a week is enough for a small business.
How Syntra can help
Syntra reads the due date on every invoice you upload and groups the unpaid ones into what is due in the next 30 days, 31-60 days and 61-90 days, so you can see upcoming commitments at a glance. It works from the documents you have uploaded, so the picture is only as complete as your records: add your fixed costs and expected client payments to get the full forecast.
Keep reading
Sources
💡 Syntra groups your unpaid invoices by due date into a 30, 60 and 90-day cash view.
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Frequently asked questions
What is a 90-day cash flow forecast?
A projection of the cash you expect to receive and pay out over the next three months, starting from your actual bank balance. It shows when your account is likely to run low.
What is the difference between profit and cash flow?
Profit counts income and costs when they are earned or incurred. Cash flow counts when money actually moves. A profitable business can still run out of cash if clients pay late.
How often should I update my forecast?
Weekly is ideal for a small business: replace expectations with actual payments, move anything that slipped and roll the forecast forward.
Can I charge interest on late payments from business customers in the UK?
Yes. For business-to-business transactions you can charge statutory interest of 8% plus the Bank of England base rate on late commercial payments.