Cash flow forecast: What it is and why it matters for your small business

Published Thursday 2 July 2026

Table of contents

• What is a cash flow forecast?
• Why cash flow forecasting matters
• What goes into a cash flow forecast?
• How to forecast cash flow
• Cash flow forecasting methods
• Choosing a forecasting period
• Tips for accurate cash flow forecasts
• Tools that help with cash flow forecasts
• Forecast cash flow with Xero
• FAQs on cash flow forecasts

Key takeaways

• A cash flow forecast estimates your future cash position by comparing expected inflows against outflows, helping you spot gaps before they become problems.
• Choosing the right forecasting method and period depends on the size and complexity of your business, with short-term forecasts offering more accuracy and long-term projections supporting strategic planning.
• Regularly updating your forecast and comparing predictions against actual figures improves accuracy over time, so you can make more confident financial decisions.
• Modern accounting software automates much of the forecasting process, reducing manual errors and giving you an up-to-date view of your finances without spreadsheet work.

What is a cash flow forecast?

A cash flow forecast is an estimate of how much money will flow in and out of your business over a set period. It shows your expected cash position at the end of that period, helping you plan ahead and make informed financial decisions.

To build one, you gather details of upcoming income and expenses, then calculate the difference. Unlike a cash flow statement, which records what's already happened, a cash flow forecast looks ahead. This makes it especially useful when you're weighing up a big purchase, planning for a quiet trading period, or deciding whether to take on new staff.

Cash flow forecasts typically cover the near future, from a few days to a few months. For a longer view, covering six months or more, you'd use a cash flow projection. The further out you look, the less precise the numbers become, but both tools play a role in keeping your finances on track.

Cash flow forecasting is particularly valuable for small businesses, where even a short period of negative cash flow can create real pressure. The Federation of Small Businesses reports that 60% of small firms say late payments hold back growth, making reliable forecasting essential for staying ahead of potential shortfalls.

Why cash flow forecasting matters

When you're focused on running your business, sudden shifts in cash flow can catch you off guard. A cash flow forecast gives you early warning, so you can act before a shortfall becomes a crisis. The UK Insolvency Service notes that insufficient cash is one of the most significant factors in companies failing, even when they're trading effectively. Research cited in the UK government's late payments crackdown estimates that around 2.8 million small firms are affected by late payments each quarter, underlining the importance of staying on top of your cash position.

Here are some of the main reasons to forecast your cash flow regularly:

• Spot potential shortfalls early. Seeing a gap weeks in advance gives you time to chase late invoices, delay non-essential spending, or arrange short-term finance before the situation becomes urgent.
• Plan major spending with confidence. Whether you're investing in equipment, hiring, or moving premises, a forecast shows how large outgoings could affect your cash position over the coming weeks and months.
• Strengthen your case with lenders and investors. Banks and investors often ask for cash flow forecasts alongside other financial reports when assessing whether to fund a business. A well-prepared forecast demonstrates that you understand your finances.
• Track seasonal patterns. Many businesses see predictable peaks and dips throughout the year. Forecasting helps you prepare for quieter months rather than being surprised by them, so you can set aside reserves when trade is strong.
• Support day-to-day decision making. Knowing your expected cash position helps you decide when to pay suppliers, when to chase payments, and when you can afford to reinvest in the business.

What goes into a cash flow forecast?

Every cash flow forecast begins with a starting balance, which is the amount of cash your business holds at the start of the period. From there, the two main inputs are:

• Money coming in: This includes customer invoices due in the coming days or weeks, and any other payments you expect to receive, such as income from selling equipment or property, tax refunds, or grants paid into your accounts
• Money going out: This includes upcoming bills and expenses, which could cover paying suppliers for stock, monthly utility bills for your business premises, staff wages, tax payments, and any loan repayments you're due to make

For each payment, you also need to know the due date. Only include payments that fall within the reporting period of your forecast (seven days ahead, 30 days ahead, and so on). You use the money coming in and going out to calculate your net cash flow and closing balance, so you can see how much your cash position is expected to change.

Getting the timing right is just as important as getting the amounts right. A customer invoice might be worth £5,000, but if it won't be paid for 60 days, it shouldn't appear in a 30-day forecast. Accuracy depends on being realistic about when money will actually arrive and leave your account.

It's also worth noting that some costs are easy to overlook. Annual insurance renewals, quarterly VAT payments, and one-off repairs can all affect your cash position if they're not included. The more thorough your list of inflows and outflows, the more reliable your forecast will be.

How to forecast cash flow

You can create your own cash flow forecast by following these steps:

1. Choose a period for your forecast, such as a week or a month ahead.
2. Write down how much cash you have at the start of that period. This is your starting balance.
3. List all of your expected cash income for the period. Include every source: customer payments, refunds, grants, and any other money due in.
4. List all of your expected cash outgoings for the period. Cover fixed costs like rent and insurance, variable costs like stock purchases, and one-off expenses like equipment repairs.
5. Subtract your expected outgoings from your income to get your net cash flow. This number shows how much your cash position has changed.
6. Add your net cash flow to your opening balance to get your closing balance. This is how much money you'll have at the end of the period.

The formula looks like this:

Net cash flow = projected cash inflows – projected cash outflows

Closing balance = opening balance + net cash flow

If your closing balance is positive, you should have enough cash to cover your commitments. If it's negative, you'll need to take action, whether that's chasing late payments, cutting back on spending, or arranging finance to bridge the gap.

Cash flow forecast example

Here's how a cash flow forecast works in practice:

A graphic designer starts March with £7,000 in cash. This is their starting balance. They want to know their cash position by 1 April, so they create a 30-day cash flow forecast.

Two clients are due to pay their invoices in the middle of March, totalling £9,000. The graphic designer has software fees, business insurance, and a mobile bill due, totalling £300. They also rent office space for £210 per month.

£9,000 income – £510 outgoings = £8,490 net cash flow

Added to the starting balance: £7,000 + £8,490 = £15,490 closing balance

This tells the graphic designer they should end March in a healthy cash position, with enough to cover upcoming expenses and potentially invest in new equipment or marketing. However, if one of those client invoices is paid late, the picture changes, which is why it's worth reviewing forecasts regularly and building in a buffer for late payments.

Cash flow forecasting methods

There are two main approaches to forecasting cash flow, and the right one for your business depends on its size and how detailed you need the forecast to be.

Direct method

The direct method tracks actual cash receipts and payments. You list every expected payment in and out for the forecast period, based on invoices, bills, and known commitments. This approach is straightforward and works well for short-term forecasts where you have good visibility of upcoming transactions.

Most small businesses find the direct method easier to set up and understand, because it uses real figures you already have to hand. It gives you a clear picture of when cash will actually arrive and leave your account.

Indirect method

The indirect method starts with your net income from the profit and loss statement and adjusts for non-cash items such as depreciation and changes in working capital. It's more commonly used for longer-term projections and by larger businesses with more complex finances.

While it gives a broader view of cash flow trends, it can be less precise for day-to-day cash planning. The indirect method is particularly useful when you need to understand the relationship between your reported profits and the actual cash available in the business.

For most small businesses, the direct method is the simpler and more practical choice. As your business grows, you may find the indirect method useful for strategic planning alongside your regular short-term forecasts.

Choosing a forecasting period

The period you forecast for should match the decisions you're trying to make. Different timeframes serve different purposes, and the right choice depends on what you need the forecast to tell you.

• Short-term (weekly or monthly): best for managing day-to-day cash, chasing late payments, and covering upcoming bills. These forecasts are the most accurate because you're working with known invoices and commitments. A weekly forecast can be particularly helpful if your business deals with tight margins or irregular income.
• Medium-term (quarterly): useful for planning seasonal fluctuations, budgeting for larger projects, or preparing for tax payments such as Making Tax Digital submissions. Quarterly forecasts strike a balance between detail and forward planning.
• Long-term (six months to a year or more): helpful for strategic decisions like expansion, hiring, or seeking investment. These rely more on estimates, so they're less precise but valuable for setting direction and demonstrating financial awareness to stakeholders.

Many businesses combine timeframes, running a detailed weekly or monthly forecast alongside a broader quarterly or annual projection. This gives you both the precision for daily decisions and the perspective for longer-term planning. If you're just getting started with forecasting, begin with a simple monthly forecast and add more timeframes as you become comfortable with the process.

Tips for accurate cash flow forecasts

A forecast is only as useful as the data behind it. These practices help keep your predictions reliable and your decisions well-informed.

• Update regularly. Review and refresh your forecast at least monthly, or weekly if your cash flow is tight. Stale forecasts based on outdated figures can lead to poor decisions. Set a recurring reminder so it becomes part of your routine.
• Be conservative with income estimates. Not every invoice will be paid on time. Build in realistic payment timelines based on your actual accounts receivable experience rather than assuming best-case scenarios. If your average customer pays in 45 days, don't assume 30. Sage research shows that 44% of invoices to small businesses are paid late, so building in a buffer is essential.
• Account for seasonal patterns. If your business has busy and quiet periods, reflect these in your forecast. Averaging income across the year can mask months where cash runs short. Look at your figures from the same period last year as a starting point.
• Compare forecasts to actuals. At the end of each period, check how your predictions measured up against what actually happened. This helps you spot where you're consistently over or underestimating, so future forecasts improve.
• Use automation where possible. Manual data entry increases the risk of errors. Accounting software with built-in forecasting pulls in real transactions automatically, reducing mistakes and saving time.

Tools that help with cash flow forecasts

It's possible to create your own cash flow forecasts manually, by writing down your inflows and outflows, or using a spreadsheet cash flow forecast template and inputting your figures. The risk with manual forecasting is that it's easy to mistype a number or include the wrong amounts in your calculation. This makes the result less accurate and less helpful for financial planning.

Modern accounting software means you don't need to learn complex forecasting techniques to get clarity. The best cash flow forecasting tools for small businesses import your bank transactions automatically, then generate predictions without the need for typing in numbers. The British Business Bank's 2026 report highlights how access to better financial tools is helping smaller firms manage cash flow more effectively.

Forecasts update automatically as new transactions come in, so you always have the most current view of your finances. Instead of calculating spreadsheet data, you can focus on growing your revenue, delivering great customer service, and supporting your team.

When choosing a forecasting tool, look for one that connects directly to your bank account, updates in real time, and presents your cash position in a clear, visual format. The less time you spend on data entry, the more time you have to act on what the forecast tells you.

Some tools also let you run different scenarios, such as "what happens if a major client pays late?" or "how would hiring a new team member affect cash flow next quarter?" This kind of scenario planning can help you prepare for uncertainty and make decisions with more confidence.

Forecast cash flow with Xero

Cash flow management is easier when you can see it from all angles. With Xero accounting software, you have the tools to look at your past, present, and future cash flow clearly. Transactions flow into Xero automatically, without you needing to manually import bank statements. With clear dashboards and visualisations, you can see your cash position at a glance. There's no confusing data to interpret; Xero does it for you.

Xero's cash flow tools also show you when bills are due and outstanding invoices become late, so you always know the next step to take to improve your financial position.

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FAQs on cash flow forecasts

Here are answers to common questions about cash flow forecasting.

What is the formula for cash flow forecasting?

The basic formula is: opening balance + projected cash inflows – projected cash outflows = closing cash balance. Your net cash flow, which shows the change in your cash position, equals projected inflows minus projected outflows.

What is the difference between a cash flow forecast and a budget?

A cash flow forecast predicts the timing and amounts of actual cash moving in and out of your business. A budget sets planned income and spending targets for a period, often including non-cash items like depreciation. Forecasts focus on when cash will be available; budgets focus on overall financial targets and performance against plan.

How often should I update a cash flow forecast?

Monthly is a good starting point for most small businesses. If your cash flow is tight or your income is irregular, weekly updates give you better visibility. The more frequently you review, the sooner you can respond to changes.

What is the difference between a cash flow forecast and a cash flow statement?

A cash flow forecast looks ahead at your projected cash position based on expected inflows and outflows. A cash flow statement looks back, recording transactions that have already happened and showing how your business earned and spent money during a specific period. Both are useful, but they serve different purposes.

Can I create a cash flow forecast without accounting software?

Yes. You can build a forecast using a simple spreadsheet or even pen and paper. List your expected income and expenses for the period, subtract outgoings from income, and add the result to your opening balance. The downside of manual forecasting is that it takes more time and leaves more room for errors, especially as your business grows.