Top Online RPGs are updated on a regular basis so keep checking back here to see who makes this list, Free online RPGs and top retail online RPGs have now been combined to make a stronger list. 

Free Online RPGs

Tibia

1)  Tibia
Uses an interesting tutor system to help newer players get in the flow of the game. Was launched back in 1997. Tibia is free, but does have a premium account available. 

2) Evony
Once known as Civony, Evony is an Addictive free online RTS where players build up cities and form alliances.  

6) Kingdom of Loathing
One of the funniest games on the entire Internet. Do not expect flashy graphics because KoL is all about satire and humor. 

7) Pardus
Great space game where you can be a pilot, trader or pirate.

8) Rubies of Eventide 
Basically the depth of a MUD with 3D graphics. The best game today for players who love to delve deep into an online RPG but prefer graphics over text. Has had periods of being offline.

9) Diablo 2
Simple game play that quickly satisfies a thirst for plenty of action and treasure makes Diablo a tough game to beat in the Online RPG realm. Throw in the online playability of Battle.net and you have the recipe for one of the greatest selling PC games of all-time. However, it can still not compete with the total gaming value of NWN.

10) Renaissance Kingdoms
Very deep online RPG with strong economic and political elements. You can run for a political office and the game's website will announce your victory if you are elected.

Honorable Mentions

 
Adventure Quest

Adventure Quest 
As can be seen by its review page, some people love it while others definitely hate it. Either way, AQ is one of the most played Online RPGs around. 

Wheel of Time MUD 
High quality MUD about one of the best fantasy novel series ever.One of the best MUDs still available.