Facebook, Instagram and WhatsApp are all experiencing outages, with users across Europe and Asia reporting issues.
Thousands of people have logged complaints on the website downdetector.com, with those using the main Facebook website and app having trouble loading their newsfeed and even logging in.
Facebook Messenger and WhatsApp are both failing to send and receive messages, and are running into other connection issues. The Instagram newsfeed is also struggling to load and update for some users.
All of the apps and services are owned and run by Facebook, which almost a month ago to the day experienced one of its longest ever outages.
The social media giant announced plans to integrate the three services back in January, prompting calls for an "urgent briefing" by the Irish data protection commissioner.
Users across the world including the US, Japan, New Zealand and parts of Europe were affected, with some unable to access any of Facebook, Instagram and WhatsApp for almost 24 hours.
As was the case on that occasion, many have turned to Twitter to voice their frustration, where global trending topics currently include #FacebookDown, #instagramdown and #whatsappdown.
Facebook, which bought Instagram in 2012 and WhatsApp in 2014, has not yet commented on the issues.(Sky News)