Contents
- What is a cash flow forecast?
- Why small businesses benefit from regular forecasting
- What to include in a cash flow forecast
- How to build a useful cash flow forecast
- Looking further ahead: the rolling forecast
- Common cash flow forecasting mistakes
- How N-Accounting can help
- Frequently asked questions
Plenty of business owners have looked at a healthy profit figure and a worryingly thin bank balance in the same week. The accounts say you are doing well. The current account says otherwise.
That gap is one of the most common sources of stress in a small business, and it has very little to do with whether you are making money.
A cash flow forecast is the tool that closes the gap. It maps out when money is actually expected to arrive in your account and when it has to leave, so you can see pressure points coming rather than meeting them on the day.
A forecast will not create cash or guarantee a smooth ride. What it gives you is notice. With a clear view of the weeks and months ahead, a looming shortfall becomes something you can plan around instead of a crisis you have to react to. This guide explains what a cash flow forecast is, what to put in one and how to build one that stays useful. It also covers the tools that keep a forecast current, and the longer rolling view that turns it from a one off exercise into ongoing visibility.
What is a cash flow forecast?
A cash flow forecast is an estimate of the money you expect to come into and go out of your business over a set period. That period might be the next four weeks, the next quarter or the next three years, depending on how much visibility you need.
The important word is cash. A forecast deals only with money actually moving in and out of the bank, on the dates it moves. That makes it different from two figures people often confuse it with.
Profit is what is left after you take your costs away from your sales over a period. It is recorded when a sale is earned and a cost is incurred, not when the money changes hands. You can invoice a large job in March, book the profit in March and not see the cash until May.
Your bank balance is a snapshot of a single moment. It tells you what you hold right now, but nothing about what is heading towards you or away from you next week.
A cash flow forecast sits between the two. It takes your expected sales and costs and places them on the dates the money will realistically move, then shows the running balance that results. This is why a profitable business can still run short. The profit is real, but the timing of the cash does not line up with the bills.
Why small businesses benefit from regular forecasting
A forecast earns its keep when it stays current and you use it to make decisions. A few of the things it helps you do:
- Spot pressure points early. If three large supplier payments and a VAT bill all fall in the same fortnight, you want to know now, not on the day.
- See the cost of late payment. When you use realistic payment dates rather than invoice dates, the effect of slow payers shows up clearly, which strengthens the case for chasing them harder.
- Plan for tax, VAT and payroll. These are date certain and non negotiable. A forecast keeps them in view so they never arrive as a surprise.
- Test investment decisions. Thinking about a new hire, a piece of equipment or a marketing push? You can see whether the cash supports it and when.
- Support conversations with lenders and advisers. Banks and investors look closely at cash flow, because it is a more honest signal of health than profit alone.
None of this means a forecast prevents every cash problem. Things change, customers go quiet, costs land early. The point is not certainty. The point is that you see the issue while you still have room to do something about it.
What to include in a cash flow forecast
A forecast does not need to be complicated to be useful. It needs five things.
Opening bank balance
Start with the actual cash you hold at the beginning of the period, across your business accounts. This is the foundation, so use the real figure from your bank rather than a rounded guess.
Expected cash in from sales, invoices and other income
List the money you expect to receive and when. The main source is usually sales, but include everything: payments against outstanding invoices, recurring income such as retainers or subscriptions, grants and tax refunds. Base sales on your order book, your pipeline and your history, not on hope.
Expected cash out for suppliers, payroll, rent, tax, finance and overheads
List the money you expect to pay and when. This covers supplier payments, wages and salaries, rent, business rates, finance and loan repayments, tax and VAT, and your regular overheads such as insurance, software, utilities and bank charges. Group them in a way that matches how your business actually spends.
Timing assumptions and known one off items
This is where most forecasts succeed or fail. Money rarely moves on the date the invoice is dated. Build in the time it actually takes your customers to pay, and the dates your own bills genuinely leave the account. Then add the irregular items that are easy to forget: an annual insurance renewal, a quarterly VAT payment, a corporation tax bill, a deposit on new equipment.
Closing balance and rolling future periods
For each period, the closing balance is the opening balance plus everything in, minus everything out. That closing figure becomes the opening balance for the next period. Repeat across your chosen horizon and you have a rolling forecast that shows the running cash position week by week or month by month.
How to build a useful cash flow forecast
Whatever you use to record it, a good forecast comes together the same way. Work through these steps.
Choose a time period that matches the decision
Match the horizon to what you are trying to see. A weekly view across the next thirteen weeks suits day to day control, especially when cash is tight or income is lumpy. A monthly view stretching further out suits planning and the bigger decisions. The strongest setup runs both, a short operational view for control and a longer rolling forecast for strategy. More on the longer view below.
Start with reliable current data
Begin from facts. Use your real opening bank balance, your actual outstanding invoices and your known commitments. The closer your starting point is to reality, the more the rest of the forecast can be trusted.
Add realistic payment timing rather than invoice dates alone
Use how customers actually pay, not how you wish they paid. If your terms are 30 days but your average customer takes 45, forecast 45. The same applies to your own outgoings. Place each item on the date the money truly moves.
Include committed and likely costs
Separate the costs you know are coming from the ones you might choose to make. Fixed commitments such as rent, loan repayments, salaries and tax are reliable and should always be in. Variable costs such as materials and utilities follow your activity level. Discretionary costs such as marketing, training or equipment can be deferred if cash gets tight, which is useful to know when you are planning.
Keep it current and compare forecast to actual
A forecast is only worth having if it stays current. Each period, replace your estimates with what actually happened, extend the forecast by one period and adjust anything that has changed. The weak point in any forecast is exactly this step, because updating figures by hand is the thing people quietly stop doing. Forecasting software that connects to your accounting system removes the chore by pulling your real invoices, bills and transactions in automatically, so the forecast updates itself and you spend your time reading it rather than rebuilding it.
A WORKED EXAMPLE
Imagine a small studio, Harbour Design, starting a month with £8,000 in the bank. It invoices a £15,000 project in month one, which feels like a strong month. But the client pays on 60 day terms, so that cash does not arrive until month three. Meanwhile the studio pays £6,000 in salaries, £1,500 in rent and overheads, and a £2,000 supplier bill during month one, all on time.
On paper, month one looks profitable. In cash terms it is £8,000 in and £9,500 out, leaving £6,500. Month two brings smaller invoices but the same fixed costs, and the balance dips towards £4,000. Only in month three, when the £15,000 finally lands, does the position recover.
Nothing here is going wrong with the business. It is winning work and making money. A live forecast that updates from the accounts would flag that month two dip on its own, well before it arrives, so Harbour Design can decide early whether to chase the invoice sooner, agree a part payment or hold a buffer, rather than discovering the squeeze on the day the salaries are due.
Looking further ahead: the rolling forecast
A short forecast keeps you in control from week to week. The bigger decisions, hiring, investment, taking on a facility or planning for growth, need a longer view than thirteen weeks can give.
This is where a rolling forecast comes in. Rolling means it always looks the same distance ahead and is re-based each period with your actual figures, so it never expires or trails off towards a single fixed year end. As one month closes, another is added at the far end and the whole picture shifts forward.
We typically build and maintain a rolling thirty six month forecast, a full three years ahead, for the clients we support this way. Three years is long enough to plan growth, investment and funding conversations with confidence, while re-basing it every month keeps it grounded in what is genuinely happening rather than a guess made once and left to age.
Maintaining a view that long by hand is hard work and easy to get wrong, which is why we run it in dedicated forecasting software rather than a spreadsheet. We put clients onto Float, which connects to your accounting system, keeps the forecast updated automatically from your live invoices, bills and transactions, lets you model what if scenarios in a few clicks and plans up to three years ahead. The right tool, paired with a forecast that someone actively maintains, is what makes a long horizon reliable rather than theoretical.
It matters most when there is more to keep track of. If your business is growing quickly, relies on overdrafts or loan facilities, runs across several entities, earns its revenue project by project, or carries significant staff and supplier commitments, the timing gets complicated and small errors can hide real problems. A maintained forecast in proper software, reviewed with an adviser, is built for exactly that.
Common cash flow forecasting mistakes
A few errors come up again and again.
- Treating a sales invoice as cash received. Revenue is earned when you do the work. Cash arrives when the customer pays, which can be weeks later. Forecast the payment date, not the invoice date.
- Forgetting irregular and annual costs. Insurance renewals, tax bills, VAT payments and annual subscriptions have a habit of landing in months you were not expecting them. Map them in.
- Letting the forecast go stale. A forecast that is not kept up to date quickly becomes fiction. Its value comes from being current, which is the strongest argument for a tool that updates itself.
- Producing a report but never acting on it. The forecast is not the goal. The decisions it prompts are the goal. If it shows a gap, the useful question is what you are going to do about it.
How N-Accounting can help
A forecast is most powerful when it is connected to the rest of your numbers and kept alive. We link cash flow forecasting to your live bookkeeping and management accounts, and we put you onto Float rather than a spreadsheet, so the forecast updates from real figures instead of relying on someone to rebuild it each month. On top of that we build and maintain a rolling thirty six month forecast, then sit down with you regularly to talk through what it is telling you and what to do next.
We have used this approach to help clients smooth out lumpy cash positions and plan with more confidence, including our cash flow support work with JL Creative. We are happy to walk you through that example.
If you would like a forecast you will actually use, set up properly and kept current, book a chat with us. We will help you build something practical and keep it working.
Frequently asked questions
What is included in a cash flow forecast?
An opening bank balance, the cash you expect to receive and when, the cash you expect to pay and when, your timing assumptions and one off items, and a closing balance that rolls into the next period.
How far ahead should a small business forecast cash flow?
It depends on the decision. A thirteen week view is the standard horizon for day to day control, long enough to give warning and short enough to stay accurate. For strategy, funding and growth you want to see further out. We build and maintain a rolling thirty six month forecast, a full three years ahead, alongside the short term view, so both the immediate and the strategic picture stay current.
Is a cash flow forecast the same as a profit forecast?
No. A profit forecast records sales and costs when they are earned or incurred. A cash flow forecast records money when it actually moves. A profitable business can still be short of cash because of timing.
Do I need software, or can I use a spreadsheet?
You can use a spreadsheet for the simplest needs, but it has to be updated by hand, which is time consuming and easy to get wrong, and it does not pull in your live figures, so it drifts out of date. We move clients onto dedicated forecasting software such as Float, which connects to your accounting system, updates automatically and plans up to three years ahead. It frees you from rebuilding the forecast and lets you focus on the decisions it points to.
How often should I update a cash flow forecast?
A forecast needs to reflect what is actually happening. With forecasting software connected to your accounts, much of this updates on its own. You still want a regular review, weekly if cash is tight and monthly if your position is steadier, to check the figures, extend the horizon and act on anything the forecast is flagging.
