As several readers point out in the comments, ESO won't be 100% free-to-play: New players will still have to make a one-time purchase of the software up front. But if you're already playing, you won't have to spend another dime starting on March 17 - regular updates and new gameplay will be offered to all players free of charge. The game will be supported by a premium membership service as well as selling stuff like DLC and "convenience and customization items" a la carte.