The forecast: Instacart's growth exploded in 2020, with sales increasing by 229.7% over 2019, for a total of $23.42 billion. But by the end of 2021, the grocery delivery company's sales will grow by a comparatively small 11.3%, which is in line with market norms.

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• Instacart is expected to continue showing strong growth over the next two years, rising to $35.00 billion in sales by 2023, but its share of the overall grocery ecommerce market will drop slightly from 21.3% to 20.0% over this time, and its share of the grocery delivery intermediary market will drop from 84.2% in 2020 to 68.2% in 2023.
• Overall, online grocery sales will make up just 9.6% of total grocery sales in 2021, but online grocery shopping is here to stay.
• As reported in our analyst note on emerging retail and ecommerce trends, "digitization will reshape grocery’s traditionally analog retail value chain. An industry once dominated by large CPG [consumer packaged goods] brands using demographic-targeted TV ads and tightly controlled distribution in physical stores is now heavily influenced by digitally native companies like Amazon, Instacart, and DoorDash."

Looking ahead: Retailers that do not work with Instacart, such as Walmart and Amazon, are growing their grocery market shares and outpacing Instacart—while large grocers that do work with Instacart, like Albertsons, are partnering with DoorDash and Uber Eats in an effort to diversify their online businesses. Instacart will lose share in the online grocery shopping market as retailers seek to diversify their online experiences.