Cost Foundations: Fixed Costs, Variable Costs, and Cost of Goods Sold

Why Costs Matter Before You Set a Price

Before a small-business owner can set a price, quote a customer, or decide whether a product is worth selling, they must understand exactly what it costs to run the business and produce what they sell. Misjudging costs is one of the most common reasons small businesses fail in their early years. This lesson builds the foundation: fixed costs, variable costs, and the cost of goods sold (COGS).

Fixed Costs

Fixed costs are expenses that stay the same every period regardless of how much you produce or sell. If you bake 10 loaves or 1,000 loaves this month, your rent does not change. Common fixed costs for a small business include:

• Rent or mortgage payment on business space
• Insurance premiums (general liability, property)
• Loan or equipment lease payments
• Salaried employee wages (staff paid a set amount per week or month)
• Utility base charges (the minimum monthly fee before usage)
• Software subscriptions (accounting software, point-of-sale systems)

Fixed costs are sometimes called overhead. Knowing your total monthly overhead tells you the minimum revenue you must bring in just to keep the doors open—before you earn a single dollar of profit.

Variable Costs

Variable costs change in direct proportion to production or sales volume. The more you make or sell, the higher these costs climb; the less you make, the lower they fall. Examples include:

• Raw materials and ingredients (flour, sugar, and butter for a bakery)
• Packaging (boxes, bags, labels)
• Hourly or piece-rate labor (workers paid per unit produced or per hour worked)
• Shipping and delivery fees charged per order
• Credit card processing fees (a percentage of each sale)
• Sales commissions paid to sales staff

Understanding variable costs helps you answer the question: What does it actually cost me to produce one more unit? That figure—the variable cost per unit—is critical for setting prices and planning production levels.

Distinguishing Fixed from Variable: A Practical Test

Ask yourself: If I sold nothing this month, would I still owe this bill?

• Yes → most likely a fixed cost.
• No, it scales with output → most likely a variable cost.

Some costs have both a fixed component and a variable component (for example, a utility bill with a base charge plus a per-kilowatt-hour rate). These are called semi-variable or mixed costs. For introductory purposes, classify them by their dominant behavior or split them into fixed and variable parts.

Total Cost Formula

Total costs for any period equal the sum of all fixed costs and all variable costs for that period:

Total Cost = Total Fixed Costs + Total Variable Costs

This simple equation is the starting point for break-even analysis and profit planning, both of which appear in later lessons.

Cost of Goods Sold (COGS)

COGS measures the direct cost of the products a business actually sold during a given period. It is reported on the income statement and subtracted from revenue to calculate gross profit.

Gross Profit = Revenue − COGS

For a business that carries physical inventory—a bakery, a retail shop, a manufacturer—COGS is calculated using the following formula:

COGS = Beginning Inventory + Purchases − Ending Inventory

• Beginning Inventory: the dollar value of goods on hand at the start of the period.
• Purchases: the cost of any additional goods or raw materials bought during the period.
• Ending Inventory: the dollar value of goods still on hand at the end of the period.

The logic is straightforward: you start with what you had, add what you brought in, and subtract what is left over. What is not left over was presumably sold (or spoiled/lost), and that is your cost of goods sold.

For a service business that carries no physical inventory, COGS typically includes the direct labor and direct supplies consumed while delivering the service—for example, the cleaning supplies and hourly wages of technicians for a cleaning company.

Why Accurate COGS Matters

If COGS is understated, gross profit looks higher than it really is, leading an owner to believe the business is more profitable than it is. If COGS is overstated, the owner may raise prices unnecessarily or cut products that are actually profitable. Accurate record-keeping—counting inventory carefully, tracking every purchase—is therefore essential business practice, not just an accounting formality.

A Note on Workplace Safety in Business Operations

Entrepreneurship courses sometimes involve hands-on settings such as school-based bakeries, kitchens, or workshops used to simulate real operations. In any such environment, standard safety practices apply: follow posted hazard warnings, use personal protective equipment (PPE) appropriate to the task (for example, food-safe gloves and slip-resistant footwear in a kitchen), keep walkways clear to prevent trips and falls, and report any unsafe conditions to the instructor immediately. For businesses that involve equipment or chemicals, employees must follow all applicable Occupational Safety and Health Administration (OSHA) guidelines and any required lockout/tagout procedures before servicing machinery. Safe operations protect people and the business from costly accidents and liability.

Connecting to Your Credential Exams

Both the Certiport ESB exam (Financial Literacy domain) and the NFTE certification assess your ability to identify cost types and interpret basic financial statements. Mastery of fixed costs, variable costs, and COGS is directly tested. Practice classifying costs quickly and computing COGS accurately so these skills become automatic before exam day.