Financial Management · Management of inventories, accounts receivable, accounts payable and cash

Cash Management and Cash Flow Forecasting for ACCA FM

Updated 11 October 2026 · Fact-checked

Cash management is planning and controlling cash so a business can pay its bills without holding too much idle cash. You forecast with a cash budget (receipts less payments, month by month). Then you set cash levels with the Baumol model (a steady cash use) or the Miller-Orr model (unpredictable cash flows).

Understand Cash Management and Cash Flow Forecasting

Cash is the most liquid asset, but it earns little or nothing. Hold too little and you cannot pay suppliers, wages or loan interest. Hold too much and you lose the return you could have earned elsewhere. Cash management is the balance between the two.

There are three classic reasons for holding cash. The transactions motive is to pay day-to-day bills. The precautionary motive is a buffer for unexpected needs. The speculative motive is to be ready for opportunities, such as a bargain purchase. Easy access to an overdraft or to short-term investments reduces the cash a firm needs to hold.

A cash budget (cash flow forecast) shows expected receipts and payments for each period, and the closing cash balance. It only includes cash movements. Depreciation, provisions and other non-cash items are left out. Credit sales produce cash later, when customers pay, not in the month of sale. Its main use is to show when you will have a surplus to invest or a deficit to fund.

Two models help set the cash balance. The Baumol model treats cash like inventory. Cash is used at a steady rate, and you top it up by selling securities. It balances the cost of each transaction against the interest lost on cash held. The Miller-Orr model is for cash flows that are uncertain. It sets a lower limit, an upper limit and a return point. You do nothing while cash stays between the limits.

The models have limits. Baumol assumes steady, predictable cash use and constant costs. Miller-Orr assumes random daily flows and a constant cost per transaction. Real cash flows are rarely this neat, so the models give guidance, not exact answers.

Key rules to remember

Baumol optimal sale size: Q = √(2 × C × S ÷ i); C = cost per transaction, S = total cash needed for the period, i = interest rate for the same period (the opportunity cost of holding cash). Q is the amount of securities to sell each time.
Baumol total cost: Total cost = (Q ÷ 2) × i + (S ÷ Q) × C; Holding cost on the average balance (Q ÷ 2) plus transaction costs. At the optimum Q the two parts are equal, which is a quick check.
Number of transactions: Transactions = S ÷ Q; Use it to find the transaction cost part of the total cost.
Miller-Orr spread: Spread = 3 × (¾ × transaction cost × variance of daily cash flows ÷ daily interest rate)^(1/3); Use a daily interest rate when the variance is of daily flows. Variance = (standard deviation)². The cube root is the 1/3 power.
Miller-Orr upper limit: Upper limit = lower limit + spread; The lower limit is set by management, for example a safety buffer or overdraft facility. It is a given in the question.
Miller-Orr return point: Return point = lower limit + (spread ÷ 3); At the upper limit, buy securities to bring cash back to the return point. At the lower limit, sell securities to return to it.
Annual rate to daily rate: Daily rate = annual rate ÷ 365 (simple), or (1 + annual rate)^(1/365) − 1 (compound); Follow the question's instruction. If none is given, state the method you use.

How to solve Cash Management and Cash Flow Forecasting questions

Use this method for any cash question. First decide whether you are asked to forecast cash or to set a cash balance policy.

1Read the requirement. Decide if it is a cash budget, a Baumol calculation, a Miller-Orr calculation, or a discussion of the results.
2For a cash budget, set up columns for each month. Lay out receipts, payments, net cash flow, opening balance and closing balance.
3Convert sales and purchases into cash. Apply credit periods, discounts, irrecoverable debts and payment lags. Take cash from the right month.
4Leave out non-cash items such as depreciation. Include capital expenditure, tax, dividends, loan interest and repayments in the month they are paid.
5For Baumol, list S, C and i for the same time period. Compute Q, then the number of transactions and the total cost if asked.
6For Miller-Orr, match the time units first. Convert the standard deviation to variance and the annual rate to a daily rate. Then compute the spread, upper limit and return point.
7State the action rule. For example, at the upper limit buy securities back down to the return point.
8Comment if asked. Name the main assumptions and say what a deficit or surplus means for borrowing or investing.

Quickest way: Rapid cash budget and model routine

When to use it: Use it in Section C when time is short, or in a Section B case with a model calculation.

Write a mini-grid for the months asked: receipts, payments, net, closing. Do not draw long workings first.
Work out each receipt line on one line of working, for example 40% × sales × 98% + 60% × last month's sales.
Cross out non-cash items before you add anything up.
For Baumol, put the numbers under the root in one go: 2 × C × S ÷ i. Then check that holding cost equals transaction cost.
For Miller-Orr, compute the inside of the bracket first. Then take the cube root, multiply by 3, and add to the lower limit.
Write the limits clearly on the last line, with the action at each limit.

Common mistakes in Cash Management and Cash Flow Forecasting

Including depreciation or other non-cash items in the cash budget.
Students copy figures from an income-statement style layout.
Fix: Ask of every line: does cash move this month? If not, leave it out.
Putting credit sales in the month of sale instead of the month of receipt.
Students rush and forget the credit period.
Fix: Draw the lag in a separate working. Check that the first month has no receipts from earlier months unless they are given.
Applying a prompt-payment discount to the wrong group of customers, or to the whole month's sales.
The percentages are mixed up in the question wording.
Fix: Take the percentage of customers who take the discount, then multiply by (1 − discount rate). Do the rest of the sales separately.
Mixing time periods in Baumol or Miller-Orr, such as annual cash need with a monthly interest rate, or daily variance with an annual rate.
The question gives data in different units.
Fix: Write the unit next to every input. Convert so they all match before calculating.
Using standard deviation instead of variance in the Miller-Orr formula.
The question gives standard deviation, and the formula needs variance.
Fix: Square the standard deviation first. The formula uses variance.
Forgetting that the return point is one third of the spread above the lower limit, not the midpoint.
Students assume the return point is the middle of the band.
Fix: Return point = lower + spread ÷ 3. The upper limit is lower + spread.

Worked examples

Example 1

A company forecasts sales of $100,000 in January, $120,000 in February and $140,000 in March. 40% of customers pay in the month of sale and take a 2% discount. The other 60% pay in the month after sale. Purchases equal 50% of the same month's sales and are paid for in the following month. Wages of $20,000 are paid each month. Equipment costing $30,000 is paid for in March. Cash at 1 February is $10,000. Prepare a cash budget for February and March.

Show the solution

February receipts: 40% × $120,000 = $48,000. After the 2% discount that is $48,000 × 0.98 = $47,040. Add 60% × $100,000 = $60,000. Total receipts = $107,040.
March receipts: 40% × $140,000 = $56,000. After discount, $56,000 × 0.98 = $54,880. Add 60% × $120,000 = $72,000. Total receipts = $126,880.
Purchases are 50% of sales: January $50,000, February $60,000. They are paid a month later, so February pays $50,000 and March pays $60,000.
February payments: $50,000 purchases + $20,000 wages = $70,000. Net cash flow = $107,040 − $70,000 = $37,040. Closing cash = $10,000 + $37,040 = $47,040.
March payments: $60,000 purchases + $20,000 wages + $30,000 equipment = $110,000. Net cash flow = $126,880 − $110,000 = $16,880. Closing cash = $47,040 + $16,880 = $63,920.

Answer: Closing cash is $47,040 at the end of February and $63,920 at the end of March. The company has a growing surplus that it could invest short term.

Example 2

A company uses the Miller-Orr model. The minimum cash balance is $5,000. The transaction cost for each purchase or sale of securities is $50. The standard deviation of daily cash flows is $1,000. The daily interest rate is 0.03%. Calculate the spread, the upper limit and the return point, and state the actions.

Show the solution

Variance = standard deviation² = 1,000² = 1,000,000.
Inside the bracket: ¾ × 50 × 1,000,000 ÷ 0.0003. First ¾ × 50 = 37.5. Then 37.5 × 1,000,000 = 37,500,000. Divide by 0.0003 to get 125,000,000,000.
Cube root of 125,000,000,000 = 5,000, because 5,000³ = 125,000,000,000.
Spread = 3 × 5,000 = $15,000.
Upper limit = 5,000 + 15,000 = $20,000.
Return point = 5,000 + 15,000 ÷ 3 = 5,000 + 5,000 = $10,000.

Answer: Spread is $15,000, upper limit is $20,000 and return point is $10,000. If cash reaches $20,000, buy $10,000 of securities. If cash falls to $5,000, sell $5,000 of securities. Do nothing in between.

Exam tips

In an objective test, read what the number is for. A Baumol question may ask for Q, the number of transactions or the total cost. Each is a different answer, and a wrong one scores zero.
Always check that units match before you use a model. This is the commonest source of a wrong answer in Miller-Orr questions.
In Section C, set out the cash budget in a clear table, with a column for each month and a total line for receipts and payments. Marks go for each correct line.
If asked to comment, link your result to action: a deficit means arrange an overdraft or delay payments, and a surplus means invest short term or pay off debt.
Know the assumptions of both models. Questions often ask when each model is suitable, or for limitations of the model you have just used.

Practice questions from Management of inventories, accounts receivable, accounts payable and cash

Cash Management and Cash Flow Forecasting in other exams

The same ground in other exams, if you are preparing for more than one or want another angle on it.

Cash Management and Cash Flow Forecasting: frequently asked questions

What is the difference between the Baumol and Miller-Orr models?

The Baumol model assumes cash is used at a steady, predictable rate and gives one optimal amount of securities to sell each time. The Miller-Orr model allows for uncertain, random cash flows and sets an upper limit, a lower limit and a return point. Baumol is simpler. Miller-Orr is more realistic.

How do I do a Baumol calculation?

Use Q = √(2 × C × S ÷ i). For example, with S = $1,440,000, C = $100 and i = 8% a year, Q = √(2 × 100 × 1,440,000 ÷ 0.08) = $60,000. That means 24 sales of securities a year, and total cost of $4,800, split equally between holding cost and transaction cost.

Why do we need a cash budget if we have a profit forecast?

Profit includes non-cash items and counts sales when made, not when paid. A business can be profitable and still run out of cash. The cash budget shows timing, so you can plan funding or investment.

Where does the lower limit come from in Miller-Orr?

Management sets it. It reflects the minimum safety balance the firm wants, perhaps related to overdraft availability or the risk of running out. In an exam question it is given to you.