Big Retailers Grow as Small Ones Struggle

Walmart, Amazon and Costco are growing faster than the rest of the industry and investing to stay ahead

- Jinjoo Lee

Big retailers already dominate Americans' lives. Their grasp on consumers is getting stronger.

The three biggest retailers by revenue in the U.S.-Costco, Walmart and Amazon-accounted for about 11% of total retail sales back in 2014, based on their reported figures measured against national retail sales data from the Commerce Department. Their share of the market has been growing since then. In their past three reported quarters, the behemoths selling everything from groceries to appliances made up about 17% of retail sales and roughly 57% of retail sales growth over that period.

Supermarkets have been a chronic casualty of the big retailers' rise. Grocery stores accounted for about two-thirds of food-athome spending in the U.S. in 2000, but their share shrank to 54% in 2023, according to the U.S. Department of Agriculture. Over the same period, warehouse clubs and supercenters such as Costco and Walmart nearly doubled their market share to 23%. Amazon hasn't grown its share of the grocery market much, but it captures a sizable share of everything else: About three-fourths of U.S. households have Amazon Prime, its paid membership program, according to a 2024 survey from Evercore.