What is Cost of Goods Sold (COGS)?

Why It Matters

Cost of Goods Sold matters because it is the foundation every other profitability metric is built on top of. Gross margin, contribution margin, and net profit margin all start from revenue minus COGS, so an inaccurate COGS figure quietly distorts every downstream number a business relies on to judge whether it is actually making money on what it sells. It also directly affects pricing decisions, since a business that underestimates its true cost per unit risks setting prices that look profitable on paper but erode margin in reality. Because COGS ties revenue to real inventory movement rather than just cash spent, it is also one of the numbers accountants and lenders scrutinize most closely when evaluating a company's financial health.

Example

A retailer starts the quarter with $50,000 in inventory, purchases $200,000 more stock during the quarter, and ends the quarter with $70,000 worth of inventory remaining. COGS is $50,000 plus $200,000, minus $70,000, which equals $180,000. Subtracting that $180,000 from quarterly revenue gives gross profit, the starting point for calculating gross margin, which is why COGS is one of the first numbers any retail or ecommerce business needs to get right before any other profitability metric can be trusted.

Frequently Asked Questions

• What is included in Cost of Goods Sold?

  COGS typically includes raw materials, manufacturing or production costs, and inbound freight or shipping needed to get the product ready for sale. It does not include marketing, sales commissions, rent, or general administrative expenses.

• How is Cost of Goods Sold different from operating expenses?

  COGS covers only the direct costs of producing what was sold, while operating expenses cover the broader costs of running the business, such as marketing, salaries not tied to production, and office overhead. Both are subtracted from revenue, but at different stages of the income statement.

• Why does inventory matter in the Cost of Goods Sold formula?

  The formula accounts for inventory because it isolates the cost of what was actually sold during the period, not everything purchased. Beginning inventory plus purchases represents everything available to sell, and subtracting ending inventory removes the portion that wasn't sold yet.

• What happens if Cost of Goods Sold is calculated incorrectly?

  An inaccurate COGS distorts gross margin and every profitability metric built on top of it, which can lead a business to believe it is more or less profitable than it actually is, and can result in mispriced products or misleading financial reports.

• How often should Cost of Goods Sold be reviewed?

  Most businesses calculate it at least monthly or quarterly for financial reporting, and it should be recalculated any time supplier costs, shipping rates, or production methods change materially, since those shifts directly change the number.