Clifford the Big Red Dog / Clifford the Big Red Dog (US) (65 episodes, 2000-2003)
Emily Elizabeth Howard / Ad Announcer / Soccer Team Announcer / Emily Elizabeth / Emily Elizabeth Howard (US) / Ad Announcer (US) / Emily / Mrs. Caroline Howard (US) / Mrs. Howard / Soccer Team Announcer (US) (65 episodes, 2000-2003)
T-Bone / T-Bone (US) (63 episodes, 2000-2003)
Cleo / Cleo (US) / Mrs. Diller / Mrs. Diller (US) (63 episodes, 2000-2003)
Clifford the Big Red Dog - (UK) / Clifford the Big Red Dog (UK) / Mac (UK) (63 episodes, 2000-2003)
Charley / Charley (US) / Charlie (57 episodes, 2000-2003)
Mr. Mark Howard / Machavelli / Ad Announcer / Mac / Mr. Dink / Mac (US) / K.C. / Mr. Mark Howard (US) / Ad Announcer (US) / Mr. Dink (US) / KC (54 episodes, 2000-2003)
Jetta / Jetta (US) / Little Clifford (US) (52 episodes, 2000-2003)
Vaz / Vaz (US) / Jetta (31 episodes, 2000-2003)
Mr. Bleakman / Mr. Bleakman (US) / Horace Bleakman / James Carty / Mr. Horace Bleakmen / Ned Graham (27 episodes, 2000-2003)
Sheriff Lewis / Mr. Bradley (US) / Mr. Kibble / Sheriff Lewis (US) (24 episodes, 2000-2003)
Samuel / Fire Chief Campbell / Samuel (UK & US) / Fire Chief Campbell (US) / Mr. Carson (US) / Mr. Carson (US) (US) / Various (23 episodes, 2000-2002)
Mrs. Bleakman / Mrs. Violet Bleakman / Mrs. Bleakman (US) / Grandma Ethel (21 episodes, 2000-2003)
Dr. Dihn / Ms. Lee / Mrs. Lee (12 episodes, 2000-2002)
Pedro / Victor / Pedro (US) / Victor (US) / Tony (11 episodes, 2000-2002)
Cleo (UK) / Cleo - (UK) / Additional Voices (UK) / Mrs. Caroline Howard (UK) / Mrs. Diller (UK) (11 episodes, 2000-2002)
Emily Elizabeth Howard (UK) / Emily Elizabeth - (UK) / Jetta Handover (UK) / Mrs. Bleakman (UK) / Additional Voices (UK) / Emily Elizabeth (UK) / Emily Elizabeth Howard (US) (11 episodes, 2000-2002)
T-Bone (UK) / T-Bone - (UK) / Additional Voices (UK) (11 episodes, 2000-2002)
Dan / Billy / Aunt Sandy / Dan (US) (8 episodes, 2001-2003)
Betty / Bob / Cosmo / Cosmo (US) / Susie (6 episodes, 2001-2003)
Boomer / Gordo / Manny / Manny (US) / Rex / Weatherman (5 episodes, 2000-2001)
Mimi (3 episodes, 2001-2003)
Mrs. Young / Monique (3 episodes, 2002)
Al the Brown Dog / Announcer Man on End / Al (3 episodes, 2000-2002)
(3 episodes, 2001)
Announcer / Husband (2 episodes, 2002)
Bruno (2 episodes, 2001-2002)
Teresa / Tonya (2 episodes, 2001-2002)
Skyscraper Jackson / Skyscraper Jackson (UK & US) (2 episodes, 2001-2002)
Ms. Martinez (2 episodes, 2001)
Hamburger (1 episode, 2003)
Oscar Owens (1 episode, 2003)
Frankie (1 episode, 2003)
Rexxington / Singing Dog (1 episode, 2003)
Mrs. Grumbly (1 episode, 2003)
Cousin Laura (1 episode, 2000)
Neighbor Lady (1 episode, 2002)
Artie (1 episode, 2003)
Deputy Wilson (1 episode, 2003)
Kiki (1 episode, 2003)
Martha Brown (1 episode, 2000)
Mr. Kobayashi (1 episode, 2002)
Frank Williams (1 episode, 2003)
Courtney Amber (1 episode, 2002)
Emily Elizabeth (1 episode, 2001)