What is Contribution Margin?
Contribution margin is the actual portion of revenue left after all variable costs that is available to cover fixed costs and ultimately generate operating profit and a sustainable operating margin percentage.
At product, customer, or business-unit level, it connects unit economics to overall value creation by showing which lines actually pay for shared overhead and which quietly erode profitability when you look at gross profit margin and net profit margin side by side.
For FP&A and corporate finance, contribution margin underpins breakeven sales volume, pricing strategy, and resource allocation across a portfolio, and is a key input into degree of operating leverage analysis.
Formula
For totals:
Per unit:
Ratio:
Example
A software company sells a subscription at $50 per month with $30 variable cost per user (hosting, payment fees, support). The contribution margin per unit is and the contribution margin ratio is .
At 1,000 subscribers, revenue is $50,000, variable costs are $30,000, and total contribution margin is $20,000, which is the pool available to cover fixed costs (salaries, R&D, G&A) and ultimately drive a healthy EBITDA margin and net profit margin.