According to Google, the option to sign up for a family plan will be made available "in the coming days" for users in the US, Canada, the UK, Australia, France and Germany. There are plans to add more countries later, and the service will be available to users on Android, iOS and the web as well. The family plans will include Google Play Music streaming for up to six people for $14.99 per month.
And, of course, Google Play Music isn't all that comes with the subscription, because YouTube Red will also be bundled. That means in addition to access to the more than 35 million songs in the Play Music library, anyone in your family plan will get ad-free access to YouTube, options for background and offline playback of YouTube videos, and the exclusive content on the way through YouTube, which may eventually include original programming.
Given that the individual subscription to Google Play Music is $9.99, this seems like a pretty easy choice for anyone who isn't a loner.
source: Android Blog