According to outage tracking website Downdetector.com, there were more than 20,000 incidents of people reporting issues with Facebook and Instagram.
Meanwhile, the social-media giant's instant messaging platform WhatsApp was also down for over 14,000 users, while Messenger was down for nearly 3,000 users.
Downdetector only tracks outages by collating status reports from a series of sources, including user-submitted errors on its platform. The outage might be affecting a larger number of users.
The Standard cannot access Facebook, Instagram and Whatsapp past midnight.
Britain's Queen Elizabeth carried out her first official engagement on Tuesday since spending a night in hospital and being ordered to rest by her doctors.