The U.S. online grocery market reached a staggering $9.6 billion in sales in November, marking a 17.8% increase over the previous year.

This growth was driven by a surge in monthly active users (MAUs), with 77.8 million households shopping for groceries online, according to Brick Meets Click’s grocery shopper survey.

“Super markets saw a major boost in their MAU base, thanks to widespread discounts on membership and subscription programs offered by both national and regional grocers in November,” said David Bishop, partner at Brick Meets Click. “While this is a positive sign for supermarkets, the competition to retain customers and capture more of their spending is only intensifying among rivals.”

The growth spanned all major fulfillment methods – pickup, delivery, and ship-to-home – all of which saw significant increases. Notably, 72% of active users reported sticking to a single fulfillment method, signaling a strong preference for simplicity and convenience, Brick Meets Click found.

This surge in online grocery shopping aligned with a broader retail trend that dominated Black Friday and Cyber Monday. The holiday shopping season was marked by a sharp increase in digital sales, with shoppers using their smartphones to make most of their purchases.

As online grocery shopping continues to expand, the stakes for retailers have never been higher. To stay competitive, grocers must meet consumer demand for convenience while adapting to a rapidly changing digital landscape.

With subscription services and hybrid shopping models on the rise, supermarkets and other retailers need to find ways to secure customer loyalty. For example, Costco (COST-0.68%) recently announced it would offer its Gold Star membership at a steep discount – an effort to boost its membership base after lower-than-expected online sales in November.