6.2 Cost-Volume-Profit (CVP) and Break-Even Analysis

Key Takeaways

  • Contribution is calculated as Sales Revenue minus Variable Costs, representing the fundamental pool of funds available to cover fixed costs and generate operational profit.
  • The Break-Even Point in units equals Total Fixed Costs divided by Contribution per Unit; in sales revenue, it equals Total Fixed Costs divided by the Contribution to Sales (C/S) Ratio.
  • Target Profit Analysis determines required sales volume using the formula: Required Sales Units = (Total Fixed Costs + Target Profit) / Contribution per Unit.
  • Margin of Safety measures the cushion between budgeted/actual sales volume and the break-even volume, expressed in units, revenue, or as a percentage of budgeted sales.
  • CVP analysis relies on key operational assumptions: linear cost and revenue behavior within the relevant range, constant sales mix for multi-product entities, and stable inventory levels.
Last updated: August 2026

Cost-Volume-Profit (CVP) Analysis examines the relationship between selling prices, sales volumes, variable costs, fixed costs, and operational profit. It provides management accountants with essential tools to assess operational risk, plan profit targets, and set pricing strategies.


The Concept of Contribution

The foundation of CVP analysis is Contribution. Contribution represents the revenue remaining after deducting all variable costs. This surplus first contributes toward paying off fixed costs; once fixed costs are fully covered, any additional contribution goes directly to net operating profit.

Unit Contribution=Selling Price per UnitVariable Cost per Unit\text{Unit Contribution} = \text{Selling Price per Unit} - \text{Variable Cost per Unit} Total Contribution=Total Sales RevenueTotal Variable Costs\text{Total Contribution} = \text{Total Sales Revenue} - \text{Total Variable Costs} Operating Profit=Total ContributionTotal Fixed Costs\text{Operating Profit} = \text{Total Contribution} - \text{Total Fixed Costs}

Contribution to Sales (C/S) Ratio

The C/S ratio (also known as the Profit-Volume or P/V ratio) measures the percentage of each revenue pound that generates contribution:

C/S Ratio=Unit ContributionSelling Price per Unit=Total ContributionTotal Sales Revenue\text{C/S Ratio} = \frac{\text{Unit Contribution}}{\text{Selling Price per Unit}} = \frac{\text{Total Contribution}}{\text{Total Sales Revenue}}


Core CVP Formulas

1. Break-Even Point (BEP)

The Break-Even Point is the sales volume at which total revenue exactly equals total costs (operating profit is zero).

  • Break-Even Point in Units: BEP (Units)=Total Fixed CostsUnit Contribution\text{BEP (Units)} = \frac{\text{Total Fixed Costs}}{\text{Unit Contribution}}

  • Break-Even Point in Revenue (£): BEP (Revenue £)=Total Fixed CostsC/S Ratio\text{BEP (Revenue £)} = \frac{\text{Total Fixed Costs}}{\text{C/S Ratio}} (Alternatively: $\text{BEP Units} \times \text{Selling Price per Unit}$)

2. Target Profit Sales Volume

To determine the sales volume required to achieve a specific target profit:

  • Required Sales in Units: Required Units=Total Fixed Costs+Target ProfitUnit Contribution\text{Required Units} = \frac{\text{Total Fixed Costs} + \text{Target Profit}}{\text{Unit Contribution}}

  • Required Sales Revenue (£): Required Revenue (£)=Total Fixed Costs+Target ProfitC/S Ratio\text{Required Revenue (£)} = \frac{\text{Total Fixed Costs} + \text{Target Profit}}{\text{C/S Ratio}}

3. Margin of Safety (MoS)

The Margin of Safety indicates the amount by which sales can fall before the company starts making a loss.

  • Margin of Safety in Units = Budgeted (or Actual) Sales Units - Break-Even Sales Units
  • Margin of Safety in Revenue (£) = Budgeted Sales Revenue - Break-Even Sales Revenue
  • Margin of Safety Percentage (%): MoS %=Budgeted Sales UnitsBreak-Even Sales UnitsBudgeted Sales Units×100%\text{MoS \%} = \frac{\text{Budgeted Sales Units} - \text{Break-Even Sales Units}}{\text{Budgeted Sales Units}} \times 100\%

Step-by-Step Comprehensive CVP Calculation Example

Company Data:

  • Selling Price: £100 per unit
  • Variable Costs: £60 per unit (Direct Material £30, Direct Labour £20, Variable Overhead £10)
  • Annual Fixed Costs: £200,000
  • Budgeted Sales Volume: 6,000 units
  • Target Operating Profit: £80,000

Step 1: Calculate Unit Contribution & C/S Ratio

  • Unit Contribution = £100 - £60 = £40
  • C/S Ratio = £40 / £100 = 0.40 (or 40%)

Step 2: Calculate Break-Even Point

  • BEP in Units = £200,000 / £40 = 5,000 units
  • BEP in Revenue = £200,000 / 0.40 = £500,000

Step 3: Calculate Margin of Safety for Budgeted Sales (6,000 units)

  • MoS in Units = 6,000 - 5,000 = 1,000 units
  • MoS Percentage = (1,000 / 6,000) × 100% = 16.67%

Step 4: Calculate Required Sales for Target Profit of £80,000

  • Required Units = (£200,000 + £80,000) / £40 = £280,000 / £40 = 7,000 units
  • Required Revenue = 7,000 × £100 = £700,000

Graphical Representation of CVP Relationships

1. Traditional Break-Even Chart

  • X-axis: Activity Level / Sales Volume (Units).
  • Y-axis: Money (£ Revenue / Costs).
  • Fixed Cost Line: Horizontal line parallel to X-axis.
  • Total Cost Line: Starts at the Fixed Cost intercept on the Y-axis and slopes upward at variable cost rate.
  • Total Revenue Line: Starts at the origin (0,0) and slopes upward at unit selling price.
  • Break-Even Point: Intersection of Total Revenue and Total Cost lines.

2. Profit-Volume (P/V) Graph

  • X-axis: Sales Volume (Units or £).
  • Y-axis: Profit (above X-axis) and Loss (below X-axis).
  • Y-intercept: Total Fixed Costs (represented as negative profit at zero sales).
  • X-intercept: Break-Even Point.
  • Slope of Line: Equals the Contribution per unit (or C/S ratio).

Underlying Assumptions and Limitations of CVP Analysis

  1. Linearity: Unit selling price, unit variable cost, and total fixed costs are assumed to remain constant across the relevant range.
  2. Fixed/Variable Categorization: All costs can be accurately divided into purely fixed or purely variable components.
  3. Single Product / Constant Sales Mix: In multi-product organizations, the mix of products sold is assumed to stay constant.
  4. Production Equals Sales: Opening and closing inventory levels are assumed to remain constant (no stock accumulation).
  5. Short-Term Horizon: CVP is suitable only for short-term operational decisions where technology and plant capacity are fixed.
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Break-Even Chart Structural Components
Total Revenue vs Total Costs Across Production Volumes (£)
Test Your Knowledge

A product sells for £25 per unit with variable costs of £15 per unit. Fixed costs are £60,000 per annum. What is the break-even point in sales revenue?

A
B
C
D
Test Your Knowledge

If budgeted sales are 8,000 units and break-even sales are 6,000 units, what is the margin of safety percentage?

A
B
C
D
Test Your Knowledge

Which of the following describes the Y-intercept on a Profit-Volume (P/V) graph?

A
B
C
D