Both desktop and smartphone devices were hit by the outages.
Facebook users were automatically logged off the app on Friday night, causing a flood of frustration and questions from the affected.
The website Downdetector.com, which monitors outages, shows waves of users complaining of log-outs. There were also some small cases where users were unable to access newsfeeds or use messenger.
Logging back into the accounts required passwords, which many did not want to provide anticipating a hack.
Deadline reported that at 7 pm US time, the incident started. Those already on the website were signed off immediately, whilst other users were unable to access the website. Both desktop and smartphone devices were hit by the outages.
Facebook App posted in response to the incident. "We're looking into reports of people being logged out and having to log in again to access their Facebook accounts. We're working to resolve this issue as quickly as possible. Thank you for your patience."