Cash Flow Forecasting for Small Business Owners

As an owner of a small business, you’re 100% confident that your product/service speaks for itself. But when it comes to money decisions, you feel like you’re left guessing. Here’s what’s likely happening: you can see how much available cash you have now and before from your financial reports. But what you really need is the ability to turn those numbers into predictions about your cash weeks or months from now, so you can make money decisions with confidence.  

Is it possible to see into the future? That’s what this guide is about. Below, learn why cash flow forecasting is a must for small business owners and how you can start forecasting today.

Why is cash flow forecasting important for small businesses

Knowing your future liquidity is key to survival because cash is usually tighter in small businesses. You’re also more prone to external factors, like a recession, dramatically affecting your cash flow. That’s what happened to almost 80% of Australian small to medium businesses (SMBs) in 2025.  

Business survival relies on strategic decisions. When you have a realistic view of your future liquidity, you can confidently answer questions like:

• Can I afford to hire another account manager?
• Should I stock up on inventory before the busy season hits?
• Is now the right time to buy that piece of equipment?
• Will moving into a bigger shopfront put too much pressure on my cash?

Here’s another benefit: you’ll be able to talk confidently with your investors, suppliers, partners, and bank, knowing you’re bringing up realistic numbers backed by real data.

Can a business be profitable and still run out of cash?

Yes. A profitable business can run into cash shortages due to slow customer payments, rapid growth draining your working capital, or non-expense cash outflows like debt and asset payments.

That’s because profitability and cash flow are different. Profitability measures whether your revenue beats your expenses over a specific period. Cash flow measures your liquidity. Profitability shows you whether your business model works based on your margins. Cash flow shows you whether your business can survive the next 30, 60, or 90 days.  

But sometimes, a profitable business runs out of cash due to a deeper margin problem. Our guide, The Profit Margin Trap: Why Revenue Growth Still Feels Tight, explains how your profitability can mask margin leaks, and what to do about it.

What causes cash flow problems for small businesses

The culprit is likely related to timing and poor cash visibility. You can run out of cash if you can’t control when money enters and leaves your business. You can’t control this if you can’t see when they enter and leave in the first place.

Here are five common, specific causes of cash flow problems for SMBs:

1. You’re managing by bank balance.

Your bank account shows you what’s available right now, not what’s already spoken for. You might think today’s balance looks great. Then you remember payroll is due tomorrow, BAS is due next week, and three supplier bills are sitting in your inbox. That’s why managing your SMB’s cash flow this way is a fast track to accidental overspending.

2. Looking backward instead of forward

Keeping your books updated is crucial, but they only tell you what happened yesterday. It won't tell you if you can afford to hire next month or survive a slow quarter. Forecasting bridges that gap. Some cash flow forecasting software even lets you test how your decisions now can impact your future cash flow.

3. Late payments and seasonal dips

Even thriving businesses get squeezed when clients take 30, 60, or 90 days to settle up. Similarly, if your business slumps over winter or Christmas, failing to plan for quiet trade can wipe out your reserves overnight.

4. Upfront growth costs

Growth is expensive. To get more clients and accommodate bigger projects, you must make smart, and at times, expensive business moves. You need forecasting here to make better timing decisions. You also learn to think differently. Instead of thinking, "Can I afford this today?" you learn to ask, "How will this impact my cash in three months?" You find out whether you need to adjust your timing, spread out costs, or delay non-essential spending if needed.

5. Forgetting irregular expenses

Some expenses like annual insurance, software renewals, equipment servicing, and tax bills don't hit every month, so they’re easier to forget until the invoice lands. If you build these into your forecast, you can save yourself from last-minute scrambles.

Cash flow forecast vs. Cash flow statement: What’s the difference?

Their time orientation. Your cash flow statement looks backward at historical data, while your cash flow forecast looks forward to predict future movements.  

Here’s a side-by-side comparison:

Using just your cash flow statement to run your business is like driving down the highway while only checking your rear-view mirror. It’s useful to see where you've been, but useless for dodging what's coming up.

How do small business owners start forecasting cash flow

Below is a step-by-step guide on how to start forecasting your cash flow on a spreadsheet or accounting software:  

Step 1: Start with your current balance

Grab the actual cash balance sitting in your bank account today. That’s your starting point for estimating how your cash position might change over time.

Step 2: List expected inflows and outflows

Map out the money you expect to move in and out over your chosen timeframe. Usual inflows and outflows include:

• ‍Inflows: Customer invoice payments, recurring retainers, asset sales, loan cash
• ‍Outflows: Wages and super, rent, software, supplier invoices, BAS/tax, fuel, utilities  

You’ll be using this formula to compute your projected cash flow:  

Opening Cash Balance + Expected Inflows - Expected Outflows = Projected Closing Balance  

Here’s an example:

• ‍Opening Balance: $40,000
• ‍Expected Inflows: + $32,000
• ‍Expected Outflows: - $28,000
• ‍Projected Closing Balance: $44,000

Doing this for each week or month gives you an ongoing view of your expected cash position.

Step 3: Choose a forecast period

Base this on the decisions you have to make. For example, if you’re concerned about managing short-term cash pressures, a weekly forecast can help. But if you’re planning for growth, budgeting, or big investments, forecast several months or even years to get a broader view.

To note: most businesses use both short-term and medium-term forecasts to balance day-to-day planning with longer-term strategy.

Step 4: Build in a buffer for the unexpected

Forecasts are based on assumptions, and things don’t always go as planned. Your client may pay late, your machines may break down, or costs may jump. Factoring a cash buffer into your forecast gives you more flexibility when real life doesn't play by the rules.

How far ahead should a small business forecast cash flow

It depends on the decisions you’re trying to make. For daily survival, you can forecast up from 4 to 13 weeks. For long-term planning, forecast up to a year or more. Try combining to balance your operational decisions with your strategic decisions.

For daily survival: Use short-term forecasts (4 - 13 weeks)

Focuses on operational decisions, like managing weekly cash, keeping on top of payroll, and monitoring your working capital. A 13-week rolling forecast is the gold standard since it covers a full quarter and exposes your weekly cash highs and lows.  

For strategy: Use long-term forecasts (6 - 12+ months)

Focus on long-term planning, like strategising for hiring, major equipment purchases, seasonal gaps, or business expansion. Each quarter, review and adjust these high-level forecasts against your actual performance.

How often should you update a cash flow forecast?

Ideally, once a month, if your business is stable with predictable revenue. But if you’re working with tight margins, a project-based business model, seasonal fluctuations, unpredictable environments, or if you’re growing fast, weekly updates might be more helpful.  

It all depends on how quickly your financial reality changes.

What happens when you can see cash flow problems coming

Act before a crunch hits. Now that you can spot a cash shortfall before it happens, you have time to figure out how to increase your cash inflow. Here are some ways to do it:

• Chase up overdue invoices or tighten payment terms on new jobs.
• Talk to key suppliers early to negotiate extended terms.
• Delay non-essential gear purchases or big cash outlays.
• Arrange an overdraft or business loan before cash gets tight.
• Adjust hiring dates so they match up with incoming revenue.

No more surprises. With a forward-looking view into your cash, you can confidently decide how to use your money today in a way that steers you and your team to growth.

Final thoughts

Visibility into how your cash moves today, yesterday, today, and tomorrow gives you the power to make informed business decisions and dodge cash shortages. You might start with a spreadsheet, but as your business grows, it’ll likely slow you down and become prone to manual data entry errors, affecting your forecast accuracy.

Automating can make you faster and more accurate. Tools like Fathom hook straight to Xero and QuickBooks, and sync with your live numbers. This cuts out manual entry and keeps your data fresh. You can also run instant "what-if" scenarios using your live numbers, helping you test your decisions before you make them. Since it combines cash flow forecasting with management reporting and financial analysis, you get full views and control of your money.

Frequently asked questions (FAQs)

1. What's the difference between a cash flow forecast and a budget?

A budget outlines what you plan to earn and spend over a set period. Meanwhile, a cash flow forecast outlines the exact timing of when you earn and spend this money. In other words, check your budget to know if you can afford an expense this year, and your forecast to know if you can afford it next Tuesday.

2. Do I need software to forecast cash flow, or can I use a spreadsheet?

Spreadsheets are fine for basic forecasts, but they take constant manual work to keep updated and are prone to data entry errors. To become efficient, consider automating your SMB’s cash flow forecasts. You save hours because it syncs straight with your books.  

3. What’s a good cash flow forecasting template for small businesses?

A good small business cash flow forecasting template tracks opening balances, cash inflows, and cash outflows to project your final cash position. The result is a static forecast. If you want a dynamic forecast, consider using forecasting software.

4. How accurate should a cash flow forecast be?

The more accurate, the better. It should be accurate enough for you to spot cash shortages and guide your strategy. Some tools like Fathom use three-way cash flow forecasting to give you precise numbers.

5. Can a new business forecast cash flow without historical data?

Yes. Build a forecast using your projected sales, estimated supplier costs, known overheads, and payment terms. As actual cash figures roll in, swap out your initial guesses to make your forecast tighter.

6. Do I need to know accounting to forecast cash flow?

Not at all. Some technologies make forecasting easy and intuitive for people of all backgrounds. For example, Fathom specialise in turning financial reports into beautiful visuals, so your entire team understands easily and you can hold more productive planning sessions. It also has an AI-powered Commentary Writer that generates insights on your financial reports.