The forecast: Walmart edged out Amazon in 2020 as the leading US grocery ecommerce retailer. We expect Walmart to continue outselling Amazon in grocery ecommerce sales through our 2023 projections.

Dive deeper:

• Walmart overtook Amazon in grocery ecommerce sales in 2020, when sales grew by more than 84% to total $27.13 billion for the big-box store. In comparison, Amazon's sales grew 63.1% in 2020, hitting $25.79 billion.
• Walmart's click-and-collect and Express Delivery services have contributed to its massive ecommerce growth.
• Amazon is limited in its ability to offer click-and-collect groceries. However, it has expanded its offerings via brick-and-mortar Whole Foods, Amazon Fresh, and Amazon Go stores.
• We didn't include Instacart in our rankings of US ecommerce retailers because it's a service that facilitates sales for grocery retailers. That said, if Instacart were to be ranked, grocery sales through the platform would've placed Instacart just below Amazon in the No. 3 spot.

Looking ahead: Although many consumers have returned to in-store shopping, grocery ecommerce will continue to grow as a retail category. Sales will hit $122.39 billion this year and will cross $200 billion in 2024.