User blog comment:G0LD3NF1RE/E3 Elder Scrolls Online Roundup/@comment-6686407-20130819232203/@comment-5469467-20130820025409

No. There is no offline mode; it's all online. The developers have no intention of adding one, either. It's an MMO, after all.

However, it will be possible to play solo to an extent. While there will always be other players around the place, you don't really need to be in a party or have much interaction with others.