Year-over-year revenue growth of Amazon and eBay 2006-2020

Amazon and eBay are direct competitors in the U.S. online shopping landscape. In 2020, Amazon achieved 38 percent year-over-year net sales revenue growth whereas eBay's year-over-year revenue increased by 19 percent. In 2015, online payment provider PayPal split from eBay to become an independent company, which had an effect on eBay’s overall revenue development.

Online marketplaces in the United States

Both eBay (launched 1995) and Amazon (launched 1994) are online shopping websites that are notable success stories of the dot-com bubble in the United States. Whereas eBay is primarily known as an online auction platform and Amazon as an online retailer, both platforms offer first- and third-party online sales. Third-party online sales usually refer to marketplace sales on a digital sales platform. Amazon generated 339 billion U.S. dollars in global online marketplace GMV, while eBay’s gross merchandise value only amounted to 90 billion U.S. dollars. Other notable online marketplace platforms in the United States are Walmart, Wish and Houzz. To further illustrate the magnitude of Amazon’s marketplace sales, one can look at the annual retail e-commerce sales distribution in the United States in 2017, when Amazon marketplace sales were estimated to account for 20 percent of total retail e-commerce sales. As of the fourth quarter of 2020, the company reported that third-party sellers accounted for 55 percent of paid unit sales.

Third-party sellers

Most third party (3P) sellers on Amazon are micro-businesses with only one to five employees. While they are also selling on marketplaces other than Amazon, the bulk of their revenues are generated via Amazon. During a 2018 survey of Amazon sellers, 47 percent stated that Amazon accounted for 81 to 100 percent of their e-commerce revenues.