While most mmorpgs release free trial periods within a year or so, En Masse released a free trial period of TERA for free accounts after a month of being released and prior to the release of their (Rather disappointing) DEMO. Some players are still upset because En Masse hasn't fixed their subscription problems and still charges players (sometimes multiple times) even when they have cancelled and keeps their credit card information:
The news information taken from their post below regarding the trial:
Now you can play TERA absolutely free for seven days with the new TERA trial. All you need is a free En Masse account to play TERA for seven days, and level up eight characters on any one server to level 23. When you convert to a paid subscription, you keep your characters.
A few restrictions apply—explained in the TERA Trial FAQ—but you’ll be able to play and enjoy almost every aspect of TERA. And, most importantly, you’ll experience our true action combat. We know it’s hard to get what makes playing TERA so different from any other MMO, and now you’ll be able to see, hear, and feel the difference for yourself.
For more details, and to get your TERA trial code, visit the Try TERA page. We’ll see you in the world of TERA!
This information can also be viewed in our blog post.