The service starts at $1.50 per month per front-line worker and then has tiers up to $4 and $8, TechCrunch reported on Tuesday.
The tool was first released in 2016 but has taken off recently.
As per the report, it took Facebook more than two years to get 2 million paid users for its tool, but it added another million users in just the last eight months.
The social network giant also announced it will add Workplace to its Portal smart screen devices for video calls.
The Workplace has been developing the use of video for a while, the aim behind this was to make a way for superiors to send out messages to workers or for people to create group chats about projects.
Facebook is now adding the video features with a number of improvement meant to let enterprises use Workplace in more ways.