Facebook users have to pay 65 cents to message anyone outside their group of friends - unless they're contacting high-profile people like Richie McCaw, who is worth almost twice that.
The social networking site trialled charging users to send private messages to people they don't have friends in common with in February and the moves have stuck.
Facebook said the charges were designed to stop users being bombarded with messages from strangers.
It's still free to send messages with friends and users who have mutual friends. But those who want to contact a non-friend can now either pay 65c to send the message directly to a person's inbox with an automatic alert, or send the message for free to a less visible folder.
Those wanting to send a message to an unknown friend have to pay the charge with a credit card. Users under 18 are barred from doing this and cannot receive unsolicited messages.