(Bloomberg) -- EBay Inc. and Shopify Inc. tumbled in premarket trading on Thursday after the e-commerce companies provided sales outlooks for the holiday quarter that fell short of Wall Street expectations. 

The stocks dropped 4.7% and 2.2%, respectively. Their lackluster outlooks also dragged down online retailer Etsy Inc., which has yet to report third-quarter results. 

EBay’s fourth-quarter sales outlook missed estimates due to expectations for a decline in gross merchandise volume after the pandemic-fueled growth in 2020, according to Bloomberg Intelligence analyst Poonam Goyal. In addition to facing tougher comparisons, Shopify also warned that supply-chain disruptions and inflation means that the current period would represent a smaller percentage of overall annual sales in 2021 than in the past.

The cautious outlooks show that e-commerce companies are grappling with a variety of challenges as economies reopen from Covid-19 lockdowns, which largely benefited their businesses. Shopify shares more than doubled in 2020, while EBay climbed 39%. 

Jefferies analyst John Colantuoni said EBay’s sales outlook was particularly disappointing given that he anticipated the company would benefit from disruptions at other retailers this holiday season. “EBay’s relevance to consumers in a normal environment is a key concern,” he added. 

Shopify analysts were additionally disappointed with the weaker-than-expected third-quarter results. Baird’s Colin Sebastian predicted that shares will remain “choppy” in the near term following the company’s first revenue miss in over five years. 

The forecasts, however, didn’t appear to weigh on the world’s biggest e-commerce retailer, Amazon.com Inc., which reports third-quarter results after the market closes Thursday. The stock gained alongside its mega-cap tech peers in premarket trading on Thursday, rising 0.6%. 

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