Study: in the US, 78% of 18-24 year olds use Snapchat, 71% use Instagram, 45% use Twitter; nearly 75% of US adults and 94% of 18-24 year olds use YouTube
A majority of Americans use Facebook and YouTube, but young adults are especially heavy users of Snapchat and Instagram
Context & Ripple Effects
Pew's March 2018 survey established a split that its own follow-ups have tracked ever since: YouTube is near-universal (94% of 18-24s, ~75% of all US adults), while Snapchat (78%) and Instagram (71%) dominate young adults and Twitter trails at 45%. A Pew teen study three months later confirmed the same hierarchy — 85% YouTube, 72% Instagram, 69% Snapchat, with Facebook at just 51%.
First-order effects
- Advertisers chasing 18-24 audiences in 2018 get a clear media plan from this data: buy YouTube first, then Snapchat and Instagram, with Twitter a secondary reach channel at 45%.
- Facebook's majority reach among US adults does not translate to the youngest cohort in Pew's related teen surveys, forcing brands to treat it as an older-skewing platform even at peak usage.
Second-order effects
- Snapchat and Instagram's high young-adult penetration made them the battleground for the next entrant: by Pew's 2022 teen survey, TikTok had taken the #2 spot at 67% while Snapchat slipped to 59% and Facebook to 32%.
- YouTube's durability across every Pew wave — 85% of teens in 2018, 95% in 2022, 93% in the 2023 teens survey — pressures every rival to add video rather than compete on text or static feeds.
Third-order effects
- Across six years of Pew fieldwork the pattern holds: each cohort ages into YouTube as a utility while the social apps beneath it churn — suggesting platform loyalty among young users is cohort-specific and replaceable, not durable.
- If the trajectory continues, the industry structurally consolidates around one video utility (YouTube) plus a rotating set of social apps, with Facebook's collapse among teens (51% in 2018 to 33% by 2023) becoming the template for any incumbent that loses the youth cohort.
The trend: US social media is settling into a YouTube-dominated video layer with fast-churning social apps underneath, where each youth cohort adopts a new leader — Snapchat and Instagram in 2018, TikTok by 2022 — while Facebook steadily exits the young end of the market.