Variable Cost
A cost that changes in direct proportion to production volume or sales activity, such as raw materials and direct labor.
What is Variable Cost?
Variable costs are expenses that fluctuate directly with changes in production volume or business activity. As output increases, total variable costs rise proportionally; as output falls, they decline. Common examples include raw materials, direct labor, packaging, sales commissions, and shipping costs. Variable costs are a key input in break-even analysis, contribution margin calculation, and pricing decisions. Total cost equals fixed costs plus variable costs, and the difference between revenue and total variable costs per unit — the contribution margin — determines how much each unit contributes to covering fixed costs and generating profit. Unlike fixed costs, variable costs are avoidable if production stops.
Example
A bakery sells artisan bread for $8 per loaf. Variable costs per loaf include $2 in flour and ingredients, $1.50 in labor, and $0.50 in packaging — totaling $4 in variable costs. The contribution margin per loaf is $8 − $4 = $4, which goes toward covering fixed costs like rent and equipment. If the bakery produces 1,000 loaves, total variable costs are $4,000; if it doubles production to 2,000 loaves, variable costs double to $8,000 — while fixed costs remain unchanged.