Operating Expense (OpEx)

What Is an Operating Expense?

An operating expense is a cost that a company pays to run its core business from day to day. These costs are not tied directly to producing a specific product or service. Instead, they cover the overhead needed to keep the business operating, such as office rent, utilities, administrative salaries, insurance, software subscriptions, advertising, and office supplies. Operating expenses appear on the income statement and are subtracted from revenue to arrive at operating income.

How Operating Expenses Are Categorized

Accountants usually separate a company's costs into two main groups. The first is cost of goods sold (COGS), which includes costs directly linked to making a product, such as raw materials and factory labor. The second is operating expenses, which include everything else needed to run the business. Some companies further divide operating expenses into selling, general, and administrative (SG&A) costs and research and development (R&D) costs.

Operating expenses can be fixed, meaning they stay roughly the same regardless of sales volume, like a lease payment. They can also be variable, meaning they rise or fall with activity, like sales commissions. Both types matter when judging how a company's costs respond to changes in demand.

Why Operating Expenses Matter to Investors

Investors watch operating expenses because they show how efficiently a company turns revenue into profit. When a business keeps these costs under control while growing sales, its operating margin may improve. When operating expenses grow faster than revenue, profit margins can shrink, even if sales are rising.

Comparing operating expenses across companies in the same industry can reveal differences in management efficiency and business models. However, the figures are most useful when viewed over several reporting periods, since a sudden jump may reflect a one-time event, such as a restructuring charge, rather than an ongoing trend.

A Simple Example

Suppose a retailer earns $1 million in revenue in a year. Its cost of goods sold is $600,000, leaving a gross profit of $400,000. If its operating expenses for rent, staff, and marketing total $250,000, its operating income is $150,000. The example is illustrative only and not a reflection of any real company.