The company shed as much as 17 percent in morning trading to a new all-time low of $5.77. Snap closed down 10.16 percent on Friday, bringing share prices to $6.28. The stock has now lost more than half its value so far in 2018 and is trading more than 70 percent below 52-week highs.
Snap beat on both the top and bottom lines Thursday, but revealed declining daily active users for the second quarter in a row — and warned the trend is likely to continue.
J.P. Morgan downgraded the stock Friday and halved its price target citing a challenging competitive landscape.
"We believe that Instagram is much more penetrated in these demographics, and it will be challenging for Snap to pull users away from Instagram," analysts at the firm wrote in a note. "We believe that Facebook and Instagram, with a much larger user and advertiser base will continue to attract incremental ad dollars in the social media space, making it difficult for Snap to gain meaningful market share."
Friday's plunge marks Snap's worst day since May, when it tanked 22 percent, and puts the stock on pace for its 16th straight week of declines.
Disclosure: CNBC parent NBCUniversal is an investor in Snap.