In simple terms
A friendly intro before the formal notes — no formulas yet.
Fuel in the tank, not miles on the map
Cash flow is the movement of money into and out of a business over a period of time. Profit is what is left when you compare the revenue earned with the costs incurred. They are not the same thing, and the gap between them is where profitable businesses quietly run out of money and die.
Picture a long road trip. Profit is the distance you plan to cover — 1,000 miles to a destination you can already see on the map. Cash is the fuel in the tank right now. You can be heading for a huge, profitable destination, but if the tank runs dry after 100 miles you are stranded at the roadside, however promising the map looks. Managing cash flow is making sure there is enough fuel in the tank at every stage of the journey, not just enough distance planned on the map. A business that forgets this can be 'profitable' all the way to insolvency.
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Start with the opening balance — the cash the business already has at the beginning of the period.
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Add up every source of money coming in during the period (cash inflows): cash sales, payments from customers who bought on credit, loans, owner's capital.
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Add up every payment going out during the period (cash outflows): wages, rent, payments to suppliers, loan repayments, buying equipment.
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Take outflows away from inflows to get net cash flow — a positive figure is a surplus, a negative figure is a deficit.
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Add net cash flow to the opening balance to get the closing balance, which is carried forward to become next period's opening balance.
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Full topic notes
Formal explanation with the rigour you need for the exam.
Cash flow is not profit
The single most important idea in this topic is that cash flow and profit are different things. Profit is calculated as revenue minus costs, and it is recorded when a sale is made and a cost is incurred — even if no money has actually changed hands yet. Cash flow records only the real movement of money: cash counts as an inflow when it is genuinely received, and as an outflow when it is genuinely paid. A firm can make a highly profitable sale on credit, so its profit rises today, while not a single dollar of cash has entered the business — the cash only arrives when the customer settles the invoice weeks later. In the meantime the firm still has to pay wages, rent and suppliers in cash. That timing gap is exactly how a profitable business runs out of money and fails.
This is why a profitable business can still fail: liquidity, not profitability, is what keeps the doors open day to day. Liquidity is the ability to pay short-term debts as they fall due. A firm whose customers all pay on 60-day credit while its own bills fall due in 30 days is chronically short of cash — and when it cannot pay, it becomes insolvent, regardless of how much profit its accounts report.
Timing: profit is recorded when revenue is earned and costs are incurred (accrual basis); cash flow is recorded when money is actually received or paid (cash basis).
Credit sales: a credit sale raises profit now but raises cash only when the customer pays — the source of most cash-flow crises.
Non-cash items: profit includes non-cash costs such as depreciation; cash flow does not.
Capital expenditure: buying a machine is a huge cash outflow now, but it reduces profit only gradually through depreciation.
Loans: receiving a loan is a big cash inflow but not profit; repaying the principal is a cash outflow but not a cost (only the interest is a cost).
The cash flow forecast
A cash flow forecast is a forward-looking estimate of the money a business expects to flow in and out, usually set out month by month. Its purpose is to spot cash shortages before they happen, so managers can arrange an overdraft or delay a payment in good time rather than being caught out. Every forecast is built from the same five parts, in the same order: it starts with the cash already held, adds everything received, subtracts everything paid out, works out the net movement, and arrives at the cash held at the end — which then becomes the start of the next month.
Net cash flow = total cash inflows − total cash outflows
Closing balance = opening balance + net cash flow
Opening balance: the cash held at the start of the month (equal to last month's closing balance).
Cash inflows: all money received during the month — cash sales, debtor receipts, loans, owner's capital.
Cash outflows: all money paid during the month — wages, rent, supplier payments, loan repayments, asset purchases.
Net cash flow: total inflows minus total outflows for the month.
Closing balance: opening balance plus net cash flow — carried forward as next month's opening balance.
Working capital and the working-capital cycle
Working capital is the finance available for the day-to-day running of the business — the money it uses to pay wages and suppliers while it waits for customers to pay. It is calculated as current assets minus current liabilities. Current assets are things expected to turn into cash within a year (cash itself, stock, and debtors); current liabilities are debts due within a year (creditors, overdrafts, short-term loans). If current liabilities exceed current assets, the firm has negative working capital and is likely to struggle to pay its bills.
Working capital = current assets − current liabilities
The working-capital cycle is the time it takes for cash spent on inputs to come back as cash from customers. The business pays cash to buy stock, holds the stock, sells it (often on credit), waits for the debtors to pay, and only then has cash again — ready to start the loop over. The longer this cycle, the more cash is tied up in stock and unpaid invoices, and the more working capital the firm needs to bridge the gap. A firm that holds stock for a long time and gives customers generous credit while paying its own suppliers quickly has a long, cash-hungry cycle; shortening it (less stock, faster collection, slower payment to suppliers) frees up cash.
Current assets: cash, stock (inventory) and debtors (accounts receivable) — expected to become cash within a year.
Current liabilities: creditors (accounts payable), overdrafts and other debts due within a year.
The cycle: cash → buy stock → sell stock (often on credit) → collect from debtors → cash again.
Longer cycle = more cash tied up: slow-selling stock and slow-paying customers lengthen the cycle and drain working capital.
Shortening the cycle frees cash: hold less stock, collect from debtors faster, pay suppliers later.
Causes of liquidity and cash-flow problems
A single negative month is not a crisis, especially if it was planned. But a persistent negative net cash flow, or a closing balance that turns negative, is a genuine liquidity problem with identifiable causes. The most common are overtrading (expanding faster than the firm can fund), poor credit control (letting customers take too long to pay), holding too much stock (tying cash up on the shelf), heavy one-off spending on fixed assets, seasonal demand that concentrates inflows in a few months, and simply having costs that are too high for the revenue coming in. Unexpected shocks — a big customer paying late or going bust, an economic downturn cutting sales — can tip an already-tight firm into insolvency.
Overtrading: growing so fast that orders outrun the working capital needed to fund stock and wages.
Poor credit control: giving customers long credit or failing to chase overdue debtors, so cash arrives too slowly.
Too much stock: cash locked up in unsold inventory that could be financing operations.
Heavy capital expenditure: a large one-off payment for equipment or premises draining the cash balance.
Seasonality and external shocks: inflows bunched into a few months, or a downturn or bad debt hitting an already-tight cash position.
Strategies to improve cash flow
The strategies to improve cash flow all do one of two things: bring cash in sooner, or push cash out later. Managing receivables means collecting from customers faster — shorter credit periods, prompt-payment discounts, credit checks and firm chasing of overdue invoices — or even selling the debts to a factoring company for immediate cash. Managing payables means the opposite for your own bills: negotiating longer credit terms with suppliers so cash leaves the business later. Reducing outflows means cutting or delaying spending — trimming costs, postponing non-essential purchases, or leasing assets rather than buying them so a large one-off outflow becomes small monthly payments. Seeking finance means arranging an overdraft, a short-term loan or new investment to cover a gap. And sale and leaseback releases cash tied up in an asset the firm owns by selling it and leasing it straight back. Each has a cost, so the right choice depends on the specific problem.
Manage receivables: shorter credit terms, prompt-payment discounts, credit checks, chasing debtors, or debt factoring — speeds cash IN. Cost: discounts and lost sales if terms are too tight.
Manage payables: negotiate longer credit from suppliers — delays cash OUT. Cost: may forfeit early-payment discounts or strain supplier goodwill.
Reduce outflows: cut or postpone spending, and lease rather than buy assets to avoid large lump-sum outflows. Cost: leasing is dearer over time; cuts may harm the business.
Seek finance: overdraft, short-term loan or new investment to bridge a gap. Cost: interest, and dilution of ownership if new investors come in.
Sale and leaseback: sell a fixed asset and lease it back for an immediate cash lump sum while still using it. Cost: loss of ownership and ongoing rent.
In Paper 2 you are usually given a cash flow forecast to complete or analyse. Two habits win marks. First, when you calculate, show the method — write 'net cash flow = inflows − outflows = 18,000 − 22,000 = −$4,000' rather than just landing a number, because the method earns a mark even if a figure slips. Second, when you suggest a strategy, tie it to the specific cause you identified in the data: if the problem is a $12,000 one-off equipment payment, recommend leasing or a loan to spread it, not a generic 'chase debtors'. Matching the fix to the diagnosed cause is where application marks live.
Common mistakes examiners penalise
Treating cash flow and profit as the same thing — a profitable business can still run out of cash. Confusing the two is the single most penalised error in this topic; profit is revenue − costs on an accrual basis, cash flow is the real movement of money.
Getting the closing-balance formula wrong — closing balance = opening balance + net cash flow. Adding net cash flow to the wrong figure, or forgetting that a NEGATIVE net cash flow is ADDED (which lowers the balance), loses accuracy marks.
Breaking the carry-forward — each month's closing balance must become the next month's opening balance. Restarting every month from zero or from the original opening balance corrupts the whole forecast.
Mishandling negatives — writing a −$3,000 net cash flow but then adding $3,000 to the opening balance. A cash deficit reduces the balance; keep the sign consistent all the way down the column.
Confusing working capital with cash flow — working capital (current assets − current liabilities) is a snapshot level at one moment; cash flow is a movement over a period. Do not use one term for the other.
Putting non-cash items in a cash flow forecast — depreciation is a cost that reduces profit but is NOT a cash outflow, so it never appears in a cash flow forecast. Likewise a loan received is a cash inflow but is not revenue.
Recommending a strategy that does not match the diagnosed cause — suggesting 'chase debtors' when the problem is a one-off equipment purchase earns little credit. The fix must address the specific cause you identified in the data.
Not showing the method — landing a final number with no working means that if one figure is wrong, there is no method mark to fall back on. Always show inflows − outflows and opening + net cash flow explicitly.
Model answer — a calculation, marked the way our engine marks it
Because 3.7 is a quantitative topic, the marks come from the numbers, not from a definition. Business Management calculation questions are marked by M/A conventions: an M (method) mark is awarded for setting the calculation up correctly — the right structure and operation — and an A (accuracy) mark is awarded for the correct final figure. Crucially, the marking is follow-through (the 'own-figure rule'): if you make one error early but carry your own figure correctly through the rest of the calculation, you still earn the later method marks. Watch how the marks below attach to each step — the method for the structure, the accuracy for the figure — and how a wrong opening figure carried correctly downward is still credited.
Where this leads
Cash flow underpins the rest of the finance unit. The forecast you build here feeds directly into sources of finance (3.1), where the choice between an overdraft, a loan, leasing and sale and leaseback is really a choice about managing cash. Working capital connects to the final accounts and liquidity ratios that measure it, and the profit-versus-cash distinction is the foundation for profitability and investment appraisal later in the course. Master the habit built here — set the calculation out clearly, show the method, keep the signs right, and say what the figure means for the business — and you have the template that earns marks on every quantitative question in Business Management.
Worked examples
See the formulas applied — reveal one step at a time, like the exam.
Worked example 1 — building a forecast. 'The Corner Slice', a new pizza takeaway, opens with $4,000 in the bank. A bank loan of $10,000 arrives in January. Forecast cash sales are: Jan 7,000, Mar $8,500. Monthly costs are rent $1,200, wages $2,500, and raw materials of 30% of that month's sales. Construct the cash flow forecast for the three months.
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Step 1 — raw material costs (30% of sales):
- Jan: 30% × 1,800
- Feb: 30% × 2,100
- Mar: 30% × 2,550
Worked example 2 — diagnosing and fixing a deficit. The forecast for 'StyleMe Ltd', a clothing retailer, shows a negative closing balance of −$1,500 in October. October figures: opening balance $2,000; cash sales $15,000; receipts from debtors $5,000; payment for new shop fittings $12,000; stock purchases $8,000; wages and rent $3,500. Identify one cause of the cash-flow problem and recommend a suitable strategy. [6]
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Step 1 — verify the figures.
- Total inflows = 5,000 =
- Total outflows = 8,000 + 23,500
- Net cash flow = 23,500 = −
- Closing balance = 3,500) = −$1,500 ✓ (matches the stated figure)
Worked example 3 (the model answer). A business has an opening cash balance of $5,000. In January cash inflows are $20,000 and cash outflows are $23,000. Calculate the net cash flow and the closing balance, and state what the figure means for the business. [4]
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Model answer. Net cash flow = total inflows − total outflows = 23,000 = −$3,000 (a cash deficit for January).
How it all connects
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Glossary
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Cash flow
The movement of money into (inflows) and out of (outflows) a business over a period of time. It measures liquidity — the ability to pay short-term debts as they fall due — not profitability.
Key takeaways
Review these before you close the topic — retrieval beats re-reading.
- ✓
Timing: profit is recorded when revenue is earned and costs are incurred (accrual basis); cash flow is recorded when money is actually received or paid (cash basis).
- ✓
Credit sales: a credit sale raises profit now but raises cash only when the customer pays — the source of most cash-flow crises.
- ✓
Non-cash items: profit includes non-cash costs such as depreciation; cash flow does not.
- ✓
Capital expenditure: buying a machine is a huge cash outflow now, but it reduces profit only gradually through depreciation.
- ✓
Loans: receiving a loan is a big cash inflow but not profit; repaying the principal is a cash outflow but not a cost (only the interest is a cost).
Practice — then mark it
The whole point: a real Cambridge question, marked mark-by-mark.
Get a Paper 2 cash-flow question marked: calculate net cash flow and the closing balance, then explain what the figures mean for the business
Get a Paper 2 cash-flow question marked: calculate net cash flow and the closing balance, then explain what the figures mean for the business
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Before you move on: do Get a Paper 2 cash-flow question marked: calculate net cash flow and the closing balance, then explain what the figures mean for the business on paper, snap a photo, and get examiner-style feedback on exactly where you win and lose marks.