Variable Operating Expenses: Examples and Calculation

Variable operating expenses are the costs that rise and fall with how much your business produces or sells. Rent and insurance premiums stay the same whether you ship ten units or ten thousand; variable costs only show up when activity happens. Knowing which of your costs behave this way, and how to calculate them, gives you real control over pricing, profitability, and cash flow.

Common Examples

Variable operating expenses look different across industries, but they share one trait: produce or sell more, and they grow; pull back, and they shrink.

Raw materials and production supplies. Every unit you manufacture consumes a measurable amount of physical input. Packaging, adhesives, and lubricants scale the same way.
Billable labor. Wages paid to contractors or hourly workers for time spent on a specific product run or project. A salaried office manager is fixed; a temp brought in for a seasonal rush is variable.
Sales commissions. Most commission structures pay a percentage of revenue, typically 5% to 20% depending on industry and deal size. Hybrid plans with a guaranteed base salary are only partly variable; the base portion stays fixed.
Credit card processing fees. Merchants generally pay 1.5% to 3.5% of each transaction.
Shipping and freight. Costs fluctuate with weight, volume, and destination.
Utilities tied to production. The electricity running an assembly line or refrigeration is variable. The base service charge on the same bill is fixed. Most commercial utility bills contain both.

Because these items tie directly to revenue-generating activity, they tend to be the first line items scrutinized during budget reviews.

Variable Operating Expenses Versus Cost of Goods Sold

This distinction trips up a lot of business owners, and getting it wrong distorts your financial statements. Cost of goods sold (COGS) captures the direct costs of producing or acquiring what you sell: raw materials, direct labor on the production line, and manufacturing overhead traceable to specific units. COGS gets subtracted from revenue at the top of the income statement to calculate gross profit.

Variable operating expenses sit further down. They include costs that fluctuate with business activity but aren’t directly embedded in the product itself — sales commissions, shipping, credit card processing fees. These get subtracted from gross profit to arrive at operating income.

The IRS draws a related line for tax purposes. Supplies used directly or indirectly in manufacturing are part of COGS and must be accounted for through inventory, not expensed immediately. Incidental supplies consumed in running the business can be deducted in the year purchased, provided you don’t keep records tracking when they’re used and the method doesn’t distort your income.¹ A bolt that becomes part of your product is COGS; the cleaning solvent you use on equipment after the shift is an operating expense.

When Costs Are Only Partly Variable

Not every expense falls neatly into fixed or variable. Semi-variable costs (also called mixed costs) have both a fixed baseline and a variable component that moves with activity. Utilities are the classic example. Your electric bill includes a fixed service charge for being connected to the grid, plus a variable charge based on kilowatt-hours actually used.

Compensation structures work the same way. A salesperson earning a $3,000 monthly base salary plus 8% commission on each sale has a fixed component ($3,000) and a variable component (the 8%). For budgeting and break-even analysis, you need to separate the two pieces. Treating a semi-variable cost as fully variable overstates how much expenses drop when revenue slows, and that kind of miscalculation breaks a cash-flow forecast.

How to Calculate Total Variable Operating Expenses

The core formula is straightforward: multiply the variable cost per unit by the total number of units produced or sold during the period.

Total Variable Cost = Variable Cost Per Unit × Total Units Produced

The hard part is getting the per-unit number right. Identify every fluctuating input that goes into completing one transaction or manufacturing one item: materials, direct labor hours, packaging, and any fees that trigger only when a sale occurs. Add those together for your variable cost per unit.

Direct Versus Indirect Variable Costs

When building the per-unit figure, separate direct variable costs from indirect ones. Direct variable costs have a clear, traceable link to a specific product or service — the lumber in a cabinet, the freelance designer hired for a client project. Indirect variable costs support multiple activities and are harder to allocate to a single unit, such as equipment maintenance that increases with production volume, or quality-control labor that scales with output but serves the entire product line.

Both types belong in your calculation, but indirect costs require an allocation method (often based on machine hours or labor hours) rather than a simple per-unit tally. Skipping indirect variable costs is one of the most common mistakes in cost analysis. It makes products look more profitable than they actually are.

Break-Even Analysis

Once you know your variable cost per unit, you can calculate how many units you need to sell before the business starts generating profit. The Small Business Administration recommends this formula:²

Break-Even Point (units) = Fixed Costs ÷ (Sales Price Per Unit − Variable Cost Per Unit)

The gap between sales price and variable cost per unit is your contribution margin per unit, the amount each sale contributes toward covering fixed costs. If your product sells for $50 and costs $30 in variable expenses to produce and deliver, contribution margin is $20. With $100,000 in annual fixed costs, you need to sell 5,000 units to break even. The SBA suggests adding a 10% buffer to your break-even target to account for unexpected expenses.²

How Production Volume Affects Variable Costs

In theory, variable costs move in lockstep with output. Double production, double the expense. In practice, the relationship is more interesting. At small volumes, you pay full price for materials and can’t negotiate much on labor. As production ramps up, bulk purchasing discounts and more efficient use of labor hours can push the variable cost per unit downward. A manufacturer buying 50,000 units of a component has far more negotiating leverage than one buying 500.

This effect has limits. Service-oriented businesses whose costs are dominated by labor, such as consulting, hospitality, and healthcare, often see little per-unit reduction as they scale, because each additional hour of service requires roughly the same labor input. Past a certain production threshold, even manufacturers hit diminishing returns: overtime wages, rushed shipping from secondary suppliers, and higher defect rates can push variable cost per unit back up.

The flip side matters just as much. When activity drops, variable expenses drop with it. If a business halts production entirely, these costs fall to zero. Fixed costs do not. Variable-heavy cost structures give you more breathing room during a downturn because expenses shrink automatically.

Where Variable Expenses Appear on an Income Statement

On a standard income statement, variable operating expenses appear in the operating expenses section, below the gross profit line. This placement keeps them separate from COGS above and from fixed overhead, giving investors and managers a clear picture of which costs scale with activity.

Subtracting all variable costs from revenue produces the contribution margin: the money available to cover fixed costs and generate profit. The contribution margin ratio (contribution margin divided by revenue) tells you what percentage of each sales dollar sticks around after variable expenses are paid. A shrinking ratio over time means variable costs are growing faster than revenue.

Public companies must follow Generally Accepted Accounting Principles when categorizing these costs.³ CEOs and CFOs of public companies must personally certify the financial information in annual and quarterly SEC filings.⁴ Miscategorizing expenses can trigger financial restatements. Under the Sarbanes-Oxley Act, an officer who knowingly certifies a report that doesn’t meet requirements faces fines up to $1 million and up to ten years in prison; willful violations carry fines up to $5 million and up to twenty years.⁵

Deducting Variable Expenses on Your Tax Return

If you operate a sole proprietorship or single-member LLC, you report variable business expenses on Schedule C of your federal tax return. The IRS provides specific line items for the most common variable categories: supplies consumed in the business (Line 22), contract labor (Line 11), commissions and fees (Line 10), car and truck expenses (Line 9), and shipping-related costs under other expenses (Line 48).⁶

A few rules catch people off guard. Supplies used directly in manufacturing belong in COGS, not on Line 22; lumping them together understates cost of goods sold and misstates gross profit. Items with a useful life significantly greater than one year must be depreciated rather than expensed as supplies, even if they feel like routine purchases.¹ Business meals are only 50% deductible, so you can’t write off the full tab from taking a client to lunch.⁶

For vehicle expenses, you choose between tracking actual costs (gas, maintenance, insurance) or using the IRS standard mileage rate of $0.70 per mile for 2025.⁶ Either way, mileage logs and receipts matter. The IRS can disallow deductions you can’t substantiate, and reconstructing a year’s worth of variable expenses from memory after an audit notice is not a position you want to be in.

Protecting Against Sudden Cost Surges

Variable costs are manageable because they’re predictable, until they aren’t. A spike in raw material prices, a tariff announcement, or a freight rate surge can blow up per-unit costs overnight. Two contractual tools help absorb that shock.

A price escalation clause ties your contract price to an objective index, allowing costs to adjust up or down based on documented market changes rather than forcing one party to absorb the full impact. In a standard fixed-price contract, the supplier bears all risk for cost increases, even unforeseen ones. An escalation clause shifts that risk into a shared, transparent framework.

Force majeure clauses get more attention but offer less protection than most people assume. Traditional force majeure language covers unforeseeable events like natural disasters and typically provides only a time extension for delayed performance, not monetary relief. Price spikes from supply-chain disruption often don’t qualify because courts may consider them foreseeable. If protection against material cost surges matters to your business, the contract needs to name unusual cost increases explicitly as a compensable event rather than relying on generic boilerplate.

1
Internal Revenue Service. Deducting Business Supply Expenses (FS-2006-28)
2
U.S. Small Business Administration. Break-Even Point
3
Office of Justice Programs. Generally Accepted Accounting Principles (GAAP) Guide Sheet
4
U.S. Securities and Exchange Commission. Exchange Act Reporting and Registration
5
U.S. Securities and Exchange Commission. Report Pursuant to Section 704 of the Sarbanes-Oxley Act of 2002
6
Internal Revenue Service. 2025 Instructions for Schedule C (Form 1040)