Variable Costs

Variable costs scale with your business activity. The more jobs you complete, the more materials you use. The more revenue you generate, the more commission you pay. When business slows, variable costs slow with it. This is the fundamental difference between variable and fixed costs — and it makes variable costs both more controllable and more predictable than fixed overhead.

Variable costs vs. fixed costs

Fixed costs are the same regardless of activity: rent, salaried staff, insurance premiums, loan payments. Variable costs only appear when there's activity to generate them. Most businesses have a mix of both. Understanding which costs are which is essential for break-even analysis, pricing decisions, and cash flow planning during slow periods.

Variable costs and pricing floors

Your variable cost per unit is the absolute floor for pricing — you can't price below it without losing money on every sale. Above that floor, every dollar of margin contributes to covering fixed costs. This is why contribution margin analysis uses variable costs rather than total costs — it identifies the actual pricing floor and the margin each sale generates toward fixed overhead and profit.

Common examples in small business

For a contractor: materials, subcontractor labor, equipment rental per job. For a retailer: cost of goods purchased for resale, shipping per order. For a service business: direct labor paid per project (if hourly), software tools billed per user. Note that labor can be fixed or variable depending on whether workers are salaried or paid per hour worked.