2021
Superstar as Self (archive footage) (1 episode)
2015
Behind Closed Doors with Natalie Morales as Himself (archive footage) (1 episode)
2010
Never Sleep Again: The Elm Street Legacy as Self (archive footage)
2006
Stanley's Dinosaur Round-Up as Great Uncle Stew (voice)
2005
Mr. Thornton Goes to Hollywood as Self (archive footage)
2004
Clifford's Really Big Movie as Clifford the Big Red Dog (voice)
2003
Bad Santa as Bob Chipeska
2003
TV Land Awards: A Celebration of Classic TV (1 episode)
2003
Time Machine: When Cowboys Were King as Self
2003
The Golden Girls: Lifetime Intimate Portrait Series as Narrator (voice)
2002
8 Simple Rules... for Dating My Teenage Daughter as Paul Hennessy (31 episodes)
2002
Tadpole as Stanley Grubman
2002
Breaking News (1 episode)
2002
Man of the Year as Bill
2002
Wednesday 9:30 (8:30 Central) (1 episode)
2001
Nuncrackers as Narrator
2001
Scrubs as Sam Dorian (1 episode)
2000
TV Funhouse as Narrator (voice) (1 episode)
2000
Terror Tract as Bob Carter
2000
Clifford the Big Red Dog
2000
Clifford the Big Red Dog as Clifford the Big Red Dog (voice) (130 episodes)
2000
TripFall as Tom Williams
2000
Lost in the Pershing Point Hotel as Christian Therapist
1999
The Early Show as Self (1 episode)
1999
Lethal Vows as David Farris
1999
Law & Order: Special Victims Unit as Dr. Richard Manning (1 episode)
1999
Family Law as Father Andrews (1 episode)
1999
It Came From the Sky as Donald Bridges
1999
Holy Joe as Joe Cass
1999
Batman Beyond as Dr. David Wheeler (voice) (1 episode)
1998
Dead Husbands as Dr. Carter Elston
1998
Bride of Chucky as Chief Warren Kincaid
1998
Loss of Faith as Bruce Simon Barker
1998
Felicity as Mr. Andrew Covington (7 episodes)
1998
I Woke Up Early the Day I Died as Robert Forrest
1998
Shadow of Doubt as Steven Mayer
1998
Chance of a Lifetime as Tom Maguire
1998
Montana as Dr. Wexler
1997
Over the Top as Justin (1 episode)
1997
Veronica's Closet as Tim Margolin (1 episode)
1997
Sink or Swim as Hank
1997
Ally McBeal as George Madison (2 episodes)
1997
The View as Self (2 episodes)
1997
A Gun, a Car, a Blonde as Duncan the Bartender
1997
Buffy the Vampire Slayer as Self (1 episode)
1997
Buffy the Vampire Slayer as Ted Buchanan (1 episode)
1997
A Child's Wish as Ed Chandler
1997
King of the Hill as Eugene Grandy (voice) (4 episodes)
1996
For Hope as Date #5 (uncredited)
1996
Mercenary as Jonas Ambler
1996
Sling Blade as Vaughan Cunningham
1996
E! True Hollywood Story (4 episodes)
1996
Harry Anderson: The Tricks of His Trade as Self
1996
Unforgivable as Paul Hegstrom
1996
Sex, Censorship and the Silver Screen as Quote Reader
1995
The Colony as Rick Knowlton
1995
Gramps as Clarke MacGruder
1995
NewsRadio as Frank Westford (1 episode)
1994
Touched by an Angel as Mike O'Conner (1 episode)
1994
Touched by an Angel as Sheriff Tom McKinsley (1 episode)
1994
Chicago Hope (1 episode)
1994
North as Ward Nelson
1993
The Only Way Out as Jeremy Carlisle
1993
Intimate Portrait as Self - Interviewee (1 episode)
1993
Intimate Portrait as Self - Narrator (voice) (1 episode)
1993
Dave's World as John Ritter (3 episodes)
1993
Late Night with Conan O'Brien as Self - Guest (1 episode)
1993
Heartbeat as Bill Grant
1992
Hearts Afire as John Hartman (54 episodes)
1992
The Larry Sanders Show as John Ritter (1 episode)
1992
Stay Tuned as Roy Knable
1992
Noises Off... as Garry Lejeune / Roger Tramplemain
1992
Fish Police (6 episodes)
1992
The Making of High Noon as Self
1992
Martin & Lewis: Their Golden Age of Comedy as Self (3 episodes)
1992
The Martin & Lewis Story: The Last Great Comedy Team as Self
1991
The Real Story of O Christmas Tree as Piney (voice)
1991
Problem Child 2 as Ben Healy
1991
The Summer My Father Grew Up as Paul
1990
The Dreamer of Oz as L. Frank Baum
1990
It as Ben Hanscom (2 episodes)
1990
Problem Child as Ben
1990
Wings as Stuart Davenport (1 episode)
1989
My Brother's Wife as Barney
1989
Anything But Love as Patrick Serreau (5 episodes)
1988
Tricks of the Trade as Donald Todsen (uncredited)
1988
Mickey's 60th Birthday as Dudley Goode
1988
LIVE with Kelly and Mark (1 episode)
1987
Real Men as Bob Wilson
1987
Hooperman as Detective Harry Hooperman (42 episodes)
1987
Prison for Children as David Royce
1987
The Last Fling as Phillip Reed
1986
A Smoky Mountain Christmas as Judge Harold Benton (uncredited)
1986
Unnatural Causes as Frank Coleman
1986
Life with Lucy as John Ritter (1 episode)
1984
All Star Party for Lucille Ball as Self
1984
Donald Duck's 50th Birthday as Self
1984
Muppet Babies (1 episode)
1984
Three's a Crowd as Jack Tripper (22 episodes)
1984
The Cosby Show as Ray Evans (1 episode)
1984
Love Thy Neighbor as Danny Loeb
1984
Strong Kids, Safe Kids as Himself
1983
Sunset Limousine as Alan O'Black
1983
Life's Most Embarrassing Moments as Self - Host (1 episode)
1982
In Love with an Older Woman as Robert
1982
Nature as Narrator (voice) (1 episode)
1982
The Fantastic Miss Piggy Show as Self
1982
The Flight of Dragons as Peter Dickinson (voice)
1982
Pray TV as Tom McPherson
1981
They All Laughed as Charles Rutledge
1981
Entertainment Tonight as Self (1 episode)
1980
Wholly Moses as Satan (The Devil)
1980
John Ritter: Being of Sound Mind and Body as Self / Various
1980
The Comeback Kid as Bubba Newman
1980
Hero at Large as Steve Nichols
1979
Americathon as President Chet Roosevelt
1979
Echoes of the Sixties: A Musical Trip as Self - Host
1979
The Ropers (1 episode)
1978
Robin Williams: Off the Wall as Himself
1978
Leave Yesterday Behind as Paul Stallings
1978
Ringo as Marty Flesh
1978
The Goldie Hawn Special as Self
1978
How to Survive the '70s and Maybe Even Bump Into Happiness as Self
1977
The Love Boat as Dale Riley (1 episode)
1977
Three's Company as Jack Tripper (171 episodes)
1976
Nickelodeon as Franklin Frank
1975
The Night That Panicked America as Walter Wingate
1975
Starsky & Hutch as Tom Cole (1 episode)
1975
The Prisoner of Second Avenue as Elevator Passenger (uncredited)
1975
The Bob Crane Show (1 episode)
1974
Petrocelli as John Oleson (1 episode)
1973
Kojak as Kenny Soames (1 episode)
1973
The Stone Killer as Hart
1972
The Streets of San Francisco (1 episode)
1972
M*A*S*H as Private Carter (1 episode)
1972
The Bob Newhart Show (1 episode)
1972
The Waltons (9 episodes)
1972
The Waltons as Rev. Ezekiel L. Henshaw (1 episode)
1972
The Waltons as Rev. Matthew Fordwick (6 episodes)
1972
The Rookies (1 episode)
1972
Evil Roy Slade as Priest (uncredited)
1971
Scandalous John as Wendell
1971
The Barefoot Executive as Roger
1971
Great Performances as Richard (1 episode)
1969
Medical Center (1 episode)
1968
Hawaii Five-O as Mike Welles (1 episode)
1968
Hawaii Five-O as Ryan Moore (1 episode)
1961
The Mike Douglas Show as Self (1 episode)
1961
The Mike Douglas Show as Self - Co-Host (1 episode)
1950
The Bob Hope Show as Self (1 episode)
1944
Golden Globe Awards as Self - Nominee (1 episode)