Current syllabus: Cost-volume-profit (CVP) analysis remains explicitly examinable in ACCA PM for September 2026 to June 2027. You may be asked about break-even, margin of safety, contribution-to-sales ratios, target profit, break-even and profit-volume charts, multi-product situations and the limitations of the model.
CVP analysis turns a question about sales volume into a question about contribution. Once each unit has covered its variable cost, the remaining contribution first pays fixed costs and then creates profit. That simple idea is the centre of every break-even calculation.
1. The contribution logic
Start with these relationships:
Contribution per unit = selling price per unit - variable cost per unit
Total contribution = sales revenue - total variable cost
Profit = total contribution - fixed costs
Break-even is the activity level at which profit is zero, so total contribution exactly equals fixed costs:
Break-even units = fixed costs / contribution per unit
Break-even sales revenue = fixed costs / contribution-to-sales ratio
Units for a target profit = (fixed costs + target profit) / contribution per unit
Do not divide fixed costs by selling price. Sales revenue must pay variable cost before it can contribute to fixed cost.
2. Complete single-product example
Product X sells for $6 per unit, has a variable cost of $2 per unit and annual fixed costs of $1,000. Budgeted sales and production are 300 units.
Calculation | Working | Answer |
|---|---|---|
Contribution per unit | $6 - $2 | $4 |
Budget profit | (300 × $4) - $1,000 | $200 |
Break-even volume | $1,000 / $4 | 250 units |
Break-even revenue | 250 × $6 | $1,500 |
Units for $300 target profit | ($1,000 + $300) / $4 | 325 units |
Practise the core CVP calculations
Enter formulas in the yellow cells, then select Show answer. Work from contribution before attempting break-even or target profit.
| Measure | Given/input | Your formula or result | Units |
| Selling price per unit | 6.00 | $ | |
| Variable cost per unit | 2.00 | $ | |
| Fixed costs | 1,000.00 | $ | |
| Budgeted sales | 300.00 | units | |
| Target profit | 300.00 | $ | |
| Contribution per unit | $ | ||
| Budget profit | $ | ||
| Break-even volume | units | ||
| Break-even revenue | $ | ||
| Units for target profit | units | ||
| Margin of safety | units | ||
| Margin of safety % | |||
| C/S ratio |
3. Margin of safety
The margin of safety measures how far expected sales can fall before the business reaches break-even:
Margin of safety = budgeted sales - break-even sales.
For Product X, the margin is 300 - 250 = 50 units. As a percentage of budgeted sales it is 50 / 300 × 100 = 16.67%. A narrow margin signals greater exposure to a forecasting error or fall in demand. A wide margin is more comfortable, although it does not by itself prove that the product is commercially attractive.
4. Contribution-to-sales ratio
The contribution-to-sales ratio (C/S ratio, sometimes called the P/V ratio) is contribution divided by sales revenue. Product X has a C/S ratio of $4 / $6 = 66.67%. Every $1 of revenue therefore contributes about $0.6667 towards fixed costs and profit, provided the assumptions remain valid.
To earn a target profit of $320, required sales revenue is:
($1,000 + $320) / 0.6667 = $1,980 (subject to rounding).
Use contribution per unit when the requirement asks for units. Use the C/S ratio when it asks for revenue.
5. Read the charts, do not merely draw them
A break-even chart plots total revenue and total cost against activity. The total-cost line starts at fixed costs; the revenue line starts at zero. Their intersection is break-even. To the left is a loss; to the right is a profit.
Interactive break-even lab
Change price, variable cost, fixed cost and expected output. Watch the break-even point and margin of safety move. Turn the profit/loss shading off and on until you can explain every region without relying on colour.
Three quick experiments: increase fixed cost; reduce the selling price towards variable cost; then raise expected output. Before each change, predict what will happen to break-even and the margin of safety.
A profit-volume chart plots profit or loss directly. Its vertical intercept is the fixed-cost loss at zero sales. The line crosses the horizontal axis at break-even and its gradient reflects contribution per unit. In an exam, label axes, the break-even point and the profit/loss regions clearly.
6. Multi-product CVP
With several products there is no single contribution per unit. Break-even revenue can still be estimated using the weighted average C/S ratio, but only if the assumed sales mix remains constant.
A business budgets the following sales:
Product | Units | Price | Variable cost | Revenue | Contribution | C/S ratio |
|---|---|---|---|---|---|---|
C | 4,800 | $5.00 | $3.75 | $24,000 | $6,000 | 25.00% |
V | 4,800 | $6.00 | $5.25 | $28,800 | $3,600 | 12.50% |
P | 12,000 | $7.00 | $4.35 | $84,000 | $31,800 | 37.86% |
Total | $136,800 | $41,400 | 30.26% |
With fixed costs of $8,000, break-even revenue at the budgeted mix is $8,000 / 0.3026 = approximately $26,435.
Do not take a simple average of the three percentages. The combined ratio is total contribution divided by total revenue. If the mix shifts towards Product P, the highest-ratio product, break-even may be reached sooner. If it shifts towards V, it may be reached later. This is why a multi-product profit-volume line based on a constant mix is straight, while a chart assuming products are sold in C/S-ratio order produces a changing slope, sometimes described as a bow-shaped line.
7. Assumptions and limitations
Selling price per unit and variable cost per unit are treated as constant within the relevant range.
Total fixed cost is treated as constant within the relevant range.
Costs can be separated reliably into fixed and variable elements.
Production is assumed to equal sales, so inventory changes do not distort the relationship.
Efficiency, productivity and technology are assumed not to change.
For multiple products, the sales mix is assumed to remain constant.
The model describes short-run financial relationships; it does not capture every qualitative or strategic factor.
A strong answer uses CVP as a decision aid and then comments on the commercial assumptions rather than presenting the calculated break-even figure as certain.
8. Exam approach
Write the contribution per unit or C/S ratio first.
Identify whether the requirement asks for units, revenue, profit or a margin of safety.
Keep contribution and profit separate.
Show formula, substitution and answer with units.
For a chart, calculate two reliable points for every straight line and label the intersection.
For a multi-product question, state the constant-mix assumption.
Interpret the result: what sales fall is tolerable, which assumption is fragile, and what action might management take?