Bluesky, the social network and X competitor, has seen its massive growth slow down in December in the U.S., according to an analysis of web traffic and mobile app daily active users by analytics firm Similarweb. After surging from 9+ million users in September to over 20 million users in November, Bluesky's growth rate slowed down to less than 10% month-over-month in December, a significant drop from the 189% growth rate it experienced in November.

The slowdown in growth is also reflected in the daily active users of the Bluesky mobile app in the U.S., which grew 12% in December, compared to 284% growth in November. Despite this slowdown, Bluesky still boasts an impressive 26.44 million users in total, and has begun adopting other X features, such as Trending Topics.

The social network's rapid growth can be attributed to a user exodus from X, formerly Twitter, following the results of the U.S. presidential election in November. As Elon Musk became more closely allied with incoming President Donald Trump and used X to promote the Trump campaign, X users unhappy with the app's latest direction moved to Bluesky in search of a more neutral platform. This move sent Bluesky's app to the top of the U.S. App Store charts in November, where it maintained a No. 1 Overall rank from Nov. 13 through Nov. 21, 2024, according to data from app intelligence provider Appfigures.

As a result, Bluesky began to attract more attention among the mainstream, with a host of Hollywood celebs, musicians, authors, and journalists joining the social network in November. However, the data now indicates that the big Bluesky bump is over, and growth is starting to normalize.

Despite the slowdown, Bluesky is still growing faster than its X rivals. According to Similarweb, Bluesky grew faster in the U.S. than another X rival, Instagram Threads, in December. That month, Bluesky's desktop and mobile web visits in the U.S. were up 9.6% month-over-month, while visits to Threads.net dropped by 1.6%. Worldwide, website visits to Bluesky's app were up a comparable 9.5% month-over-month in December 2024, ahead of Threads growth of 5.7% and X's 2.4%, Similarweb's data shows.

However, Bluesky's larger audience means the app now faces growing pains, including user protests over moderation policies, issues with bots joining the platform, and other moves from bad actors like user name squatting and impersonation, which the company attempted to address in a recent app update.

Despite these challenges, Bluesky still had a massive 2024 overall, with year-over-year growth of 930% worldwide, based on website visits, and two-year growth of 30,564%. As the social network continues to navigate its growing pains, it remains to be seen whether it can maintain its lead over X rivals and establish itself as a major player in the social media landscape.