http://m.gamestar.de/artikel/the-elder-scrolls-online,3026853.html
In an interview with Gamestar, Matt Firor, the general manager of zenimax online, has confirmed the Elder Scrolls online will have subscription fees, stating that "one small monthly fee for 100% access to the game fits the IP and the game much better than a system where you have to pay for features and access as you play"
At the moment the planned monthly fee is $14.99 or your regional equivalent, with the developers promising high-quality content updates after the launch of the game.