WOW - character Slots to Realms? : World of Warcraft General Discussions

Vaneras from Blizzard replies to a player who asks, "Are there any plans to implement more character slots to character screen on realms?"...

The new hero class will indeed take a character slot, however there are no plans to add more character slots at this point in time.

So if all your character slots are in use, then the best suggestion right now would be strategic deletion or transfer of characters if you want to add the new Death Knight to your repertoire. This is similar to when the Draenei and Blood Elves were added to the game, so if you had used all your character slots back then, then the immediate solution would be to repeat what you did back then to solve this current conundrum.

Thanks