X, formerly Twitter, experienced a decline in its U.S. user base, dropping to an 18% share by August 2023. Conversely, Meta’s user engagement broadened from 73% to 77% between 2021 and 2023, with their new offering, Instagram Threads, securing 11% of users. While most platforms, including Reddit and LinkedIn, maintained their rankings with minor growth, user loyalty metrics highlighted Facebook and Instagram’s consistent user retention. In demographic insights, LinkedIn and Nextdoor attract highly educated users, while generational data indicates Gen Z favors Twitch and Discord. These user behavior trends are crucial for technology marketers crafting targeted strategies. This TUPdate reports on the percentage of online Americans who have visited each of the major social networking sites in 2021 through 2023 and profiles each site’s users by key demographics.