• Costco average gross margin for 2023 was 12.2%, a 0.89% increase from 2022.
• Costco average gross margin for 2022 was 12.31%, a 4.87% decline from 2021.
• Costco average gross margin for 2021 was 12.94%, a 0.99% decline from 2020.

Gross margin can be defined as a company's total sales revenue minus its cost of goods sold, divided by the total sales revenue, expressed as a percentage.