Amazon tops Wal-Mart in this ranking By: MarketWatch February 09, 2015 at 17:02 PM EST Wal-Mart is the largest retailer in the U.S. by sales, but when it comes to America’s favorite, Amazon.com dominates. Read More >> Related Stocks: Amazon.com J C Penney Company Inc Kohl's Corp Macy's Target Corp Wal-Mart Stores, Inc.