You cannot use Messenger without signing up for a Facebook account

While most of Messengers users have Facebook accounts, there is still a portion of people who don't want to have a Facebook account, but still want to use the messaging service.

Times are now changing, and those portion of people will now be required to sign up to Facebook to access Messenger. According to the website's Help Center, "you'll need to create a Facebook account to use Messenger." Originally, users could sign up to Messenger by just entering their phone number and not having to worry about having a Facebook account. That option has now been revoked.

VentureBeat has also got the news confirmed to them via Facebook, here's what they said "If you're new to Messenger, you'll notice that you need a Facebook account to chat with friends and close connections. We found that the vast majority of people who use Messenger already log in through Facebook and we want to simplify the process."

This move by Facebook is most likely a step towards them unifying all their platforms messaging services (Instagram, WhatsApp) into one messaging giant. This unified platform would allow users of all Facebook-owned apps to be able to send messages across different apps, regardless of their origin. This would obviously only be the case for apps that are owned and controlled by Facebook.