Hey Arnold!

Helga Pataki (voice) (186 episodes)

Gerald Johanssen (voice) (186 episodes)

Grandpa Phil (voice) (152 episodes) / Grandpa Phil / Nick Vermicelli (voice) (1 episode) / Grandpa Phil / Chicken Man (voice) (1 episode) / Grandpa Phil / Grandpa Phil's Father / Jolly Olly Man (voice) (1 episode) / Nick Vermicelli (voice) (1 episode) / Grandpa Phil / Reporter (voice) (1 episode) / Grandpa Phil / Cop #1 (voice) (1 episode) / Grandpa Phil / Judge (voice) (1 episode) / Delivery Man (voice) (1 episode) / Animal Control Officer (voice) (1 episode) / Grandpa Phil / Nolo (voice) (1 episode) / Big Arnold (voice) (1 episode)

Harold Berman (voice) (107 episodes) / Harold Berman(voice) (37 episodes) / Harold Berman (voice; uncredited) (1 episode) / Joey (voice) (1 episode) / Harold Berman / Boy on Bicycle (voice) (1 episode) / Harold Berman / Robert (voice) (1 episode) / Harold Berman / Iggy (voice) (1 episode)

Phoebe Heyerdahl (voice) (102 episodes) / Phoebe Heyerdahl / Girl (voice) (1 episode) / Phoebe Heyerdahl / Italian Girl / French Girl (voice) (1 episode) / Phoebe Heyerdahl / Clerk (voice) (1 episode) / Phoebe Heyerdahl / Joy (voice) (1 episode) / Patrice (voice) (1 episode) / Phoebe Heyerdahl / Kid #2 (1 episode) / Phoebe Heyerdahl / Woman (voice) (1 episode) / Phoebe Heyerdahl / Worker #2 (voice) (1 episode) / Phoebe Heyerdahl / Ruth P. McDougal (voice) (1 episode)

Stinky Peterson (voice) (84 episodes) / Stinky Peterson / Kyle (voice) (2 episodes) / Stinky Peterson / Bratty Kid #1 (voice) (1 episode) / Stinky Peterson (voice; uncredited) (1 episode)

Arnold (voice) (75 episodes) / Ludwig (voice) (1 episode)

Arnold (voice) (73 episodes)

Rhonda Wellington Lloyd (voice) (65 episodes) / Rhonda Wellington Lloyd / Mary (voice) (1 episode)

Arnold (voice) (50 episodes) / Wolfgang (voice) (4 episodes) / Wolfgang / French Boy (voice) (1 episode) / Arnold (singing voice) (1 episode)

Sid (voice) (45 episodes) / Billy (voice) (1 episode) / Sid / Robert (voice) (1 episode)