Amazon’s third-party marketplace has approximately 25% market share of the total US e-commerce spending. As per eMarketer data, in 2021, Amazon held up to 41.4% of all the e-commerce sales in the US. Amazon would have been the largest retailer if its third-party marketplace were independent. After Amazon Marketplace, Amazon retailer has 17% of the market share. Walmart’s market share is around 7-8%. eBay, Apple, and The Home Depot have been losing market share in the past years due to cut-throat competition from Amazon and Walmart. Although Shopify is not on the list, it would have been the third biggest retailer if all the Shopify vendors were one retailer.