Facebook says it is testing a service that will charge users $1 to guarantee that messages they send to people they are not connected to arrive in users' inboxes, rather than in an often-ignored folder called "other."

Launched in 2011, the "other" folder is where Facebook routes messages it deems less relevant. Not quite spam, these include messages from people you most likely don't know, based on Facebook's reading of your social connections. Many users ignore this folder.

Now, users will be able to pay $1 to route their messages to non-friends. Facebook said Thursday that it is testing the service with a small percentage of individuals - not businesses - in the US.

"For example, if you want to send a message to someone you heard speak at an event but are not friends with, or if you want to message someone about a job opportunity, you can use this feature to reach their Inbox," Facebook said in an online post.

"For the receiver, this test allows them to hear from people who have an important message to send them."

The company says charging for messages could help discourage spammers.

In October, Facebook unveiled another feature that lets users pay if they want more people to read their updates. For $7, users can promote a post to their friends, just as advertisers do.