Spotify doesn't want Premium subscribers sharing their accounts with friends, because it ultimately means the company is losing money in lost subscriptions. The company sent an email asking Family subscribers for their home address as a way of cracking down on account sharing, and now its trying to keep customers happy by creating a cheaper subscription for two people.
According to Engadget, Spotify is testing a program called Spotify Premium Duo, which gives subscribers two Premium accounts for $14 per month, as opposed to an individual Premium account which costs $9.99. If you have a partner, roommate, or family member living at the same address who wants to go Premium, it's a way to save $6 a month.
A Premium Spotify account allows you to download music to listen to any time, skip as many songs as you want, and doesn't have ads. The Duo plan offers the same perks (while keeping each account separate), but also has the option for a Duo Mix playlist, an auto-generated playlist that plays the music you both like.
The subscription plan is currently limited to listeners in Colombia, Chile, Denmark, Ireland, and Poland. But if it's successful, chances are it'll roll out to the rest of Spotify's markets.