All 257 actors in both 24 and ER
257 actors have appeared in both 24 and ER, across 535 episodes. The most-credited is Leland Orser, Martin Collier in 24 and Dr. Lucien Dubenko in ER.
| Actor | In 24 | In ER | Eps | Eps |
|---|---|---|---|---|
| Leland Orser | Martin Collier | Dr. Lucien Dubenko | 4 | 61 |
| Jude Ciccolella | Mike Novick | Roach Coach Charlie | 58 | 1 |
| Glenn Morshower | Agent Aaron Pierce | Rick Decoyte | 49 | 1 |
| Reiko Aylesworth | Michelle Dessler | Chaplain Julia Dupree | 38 | 7 |
| Paul McCrane | Graem | Dr. Robert Romano | 8 | 30 |
| Gregory Itzin | Charles Logan | Burn Doctor | 20 | 1 |
| Penny Johnson Jerald | Sherry Palmer | Nurse Practitioner Lynette Evans | 32 | 9 |
| John Terry | Bob Warner | Dr. David 'Div' Cvetic | 12 | 8 |
| Kathleen Wilhoite | Lauren Proctor | Chloe Lewis | 1 | 19 |
| Sara Gilbert | Paula Schaeffer | Dr. Jane Figler | 5 | 15 |
| Lourdes Benedicto | Carrie Turner | Rena Trujillo | 11 | 5 |
| Tzi Ma | Cheng Zhi | Mr. Yeung | 14 | 1 |
| James Cromwell | Phillip Bauer | Bishop Stewart | 8 | 4 |
| Ryan Cutrona | Admiral John Smith | Wilson | 12 | 1 |
| Daniel Bess | Rick Allen | Marshall | 18 | 1 |
| Harry Lennix | Walid Al-Rezani | Dr. Greg Fischer | 6 | 6 |
| Kari Matchett | Lisa Miller | Dr. Skye Wexler | 10 | 5 |
| Kim Raver | Audrey Raines | Kim Zambrano | 4 | 1 |
| Michelle C. Bonilla | Reporter | Paramedic Christine Harms | 2 | 58 |
| Jesse Borrego | Gael Ortega | Javier, HIV-Positive Patient | 14 | 4 |
| Xander Berkeley | George Mason | Detective Wilson | 12 | 1 |
| Željko Ivanek | Andre Drazen | Bruce Resnick | 15 | 1 |
| Daniel Dae Kim | Agent Tom Baker | Ken Sung | 11 | 4 |
| Sandrine Holt | Evelyn Martin | Drew | 10 | 1 |
| Stephen Spinella | Miles Papazian | Henry Lotery | 10 | 1 |
| Christopher Amitrano | Brennan | Officer Hollis | 2 | 12 |
| Carlos Gómez | Luis Annicon | Paramedic Raul Melendez | 3 | 6 |
| Chad Lowe | Reed Pollock | George Henry | 8 | 4 |
| Mare Winningham | Elaine Al-Zacar | Dr. Amanda Lee | 2 | 4 |
| Paul Blackthorne | Stephen Saunders | Dr. Jeremy Lawson | 10 | 5 |
| Shohreh Aghdashloo | Dina Araz | Riza Kardatay | 11 | 1 |
| Nestor Serrano | Navi Araz | David Torres, CDC | 10 | 1 |
| Julian Morris | Agent Owens | Dr. Andrew Wade | 6 | 7 |
| Lawrence Monoson | Gary | Dean Rollins | 1 | 4 |
| Alan Dale | Vice President Jim Prescott | Al Patterson | 8 | 3 |
| Tanya Wright | Patty Brooks | Megan Strand | 8 | 1 |
| Kal Penn | Ahmed Amar | Narajan | 4 | 1 |
| Megan Gallagher | Gillian Wallace | Kathy Snyder | 4 | 2 |
| Misha Collins | Alexis Drazen | Bret | 7 | 2 |
| Lesley Fera | Angela | Helen Kolber | 5 | 1 |
| Scott Michael Campbell | Brady Hauser | EMT Reilly Brown | 1 | 7 |
| Thomas Vincent Kelly | Dr. Marc Besson | Jeffrey Macauley | 7 | 1 |
| Anil Kumar | Kalil Hasan | Benazir | 5 | 1 |
| Megalyn Echikunwoke | Nicole Palmer | Terry Welch | 6 | 1 |
| Michael Angarano | Scott Wallace | Zack | 4 | 1 |
| Robert Maffia | Andrei | Perfusionist | 3 | 2 |
| Steven Culp | Agent Ted Simmons | Dave Spencer, Dr. Charles Cameron | 2 | 5 |
| Jamie McShane | Gerry Whitehorn | Josh Rushing | 6 | 1 |
| Francesco Quinn | Syed Ali | Dr. Alfonso Ramirez | 5 | 1 |
| Eyal Podell | Ryan Burnett | Sammo | 4 | 1 |
| Matthew Yang King | CTU Agent King | Rick | 4 | 1 |
| Matthew Carey | Dan Mounts | David | 6 | 1 |
| Silas Weir Mitchell | Eli | Luis, Marcus Hainey | 5 | 2 |
| Maury Sterling | Kozelek | Dr. Nelson | 1 | 5 |
| Andi Chapman | Rosa | Joanie Albright | 3 | 2 |
| Gregg Henry | Jonathan Wallace | Officer Mark Downey | 4 | 1 |
| Kathleen Gati | Anya Suvarov | Stacy Coleman | 4 | 1 |
| Michael Cavanaugh | Homeland Security Director Joseph O'Laughlin | Suzanne's Dad | 4 | 1 |
| Tobin Bell | Peter Kingsley | Dr. Gary Wertz | 4 | 1 |
| Nick Offerman | Marcus | Rog | 3 | 1 |
| Andy Umberger | Dr. Linzer | Dr. David Harvey | 3 | 2 |
| James C. Victor | Agent Turner | Patrick | 4 | 1 |
| John Prosky | Dr. George Ferragamo | Mr. Brooks | 1 | 4 |
| Stana Katic | Collette Stenger | Blaire Collins | 3 | 2 |
| Vincent Angell | Dr. Phil Parslow | Det. Graham | 4 | 1 |
| Stephanie Erb | Sue | Mrs. Kinney | 2 | 1 |
| Raphael Sbarge | Ray Wallace | Mr. Kirkendall | 2 | 2 |
| Tony Plana | Omar | Priest | 3 | 1 |
| Joe D'Angerio | Osterlind | Rezek | 4 | 1 |
| Michael McGrady | CHP Officer Brown | Fire Captain Davis | 4 | 1 |
| Albert Hall | Alan Milliken | James Anderson | 4 | 1 |
| Andrew Hawkes | Scott Evans | Hagan | 2 | 1 |
| Butch Klein | Agent Richards | Wynn | 3 | 1 |
| C. Thomas Howell | Dr. Barry Landes | Vincent Jansen | 2 | 1 |
| Christian Svensson | Harris | Sheriff Pohler | 3 | 1 |
| Currie Graham | Ted Cofell | James | 2 | 1 |
| Dylan Haggerty | N.E.S.T. Tech #1 | Coach Yazerski | 3 | 1 |
| Jenette Goldstein | Rae Plachecki | Helicopter Medic, Judy Stiles | 2 | 2 |
| Michael Cudlitz | Agent Rick Phillips | Lang | 3 | 1 |
| Michael Gaston | Gen. David Brucker | U.S. Marshal Rick Cromley | 2 | 1 |
| Josh Cruze | Oriol | Boss | 5 | 1 |
| Freda Foh Shen | Doctor | Audiologist | 2 | 3 |
| Michael Reilly Burke | Bruce Carson | Dick White | 3 | 1 |
| Tom Wright | Admiral Kirkland | Wharton | 2 | 2 |
| Tracy Howe | Agent Justin Adams | Gary | 3 | 1 |
| William Bumiller | Agent Lowry | NASA lecturer | 3 | 1 |
| Yorgo Constantine | Mikhail | Trekkie | 3 | 1 |
| Peter Gregory | Dr. Spire | Mr. Phillips | 2 | 1 |
| John Lacy | Marshal Holtzman | Kevin Poole | 1 | 1 |
| Ted Marcoux | Sam Singer | Derek Fossen | 2 | 2 |
| Lucinda Jenney | Helen Singer | Allison | 4 | 1 |
| Larry Sullivan | SS Agent | Martin Pryor | 2 | 1 |
| Mark Rolston | Bruce Foxton | Officer Thomas | 2 | 1 |
| Bruce Nozick | Division Agent | Craig Simon | 2 | 2 |
| Conor O'Farrell | Ted Packard | Richard Abbott | 2 | 2 |
| Henri Lubatti | Jovan Myovic | Victor | 3 | 1 |
| Robert Cicchini | Howard Bern | Channel 5 Chopper Reporter | 3 | 1 |
| Albie Selznick | John Reiss | Mr. Lanford | 2 | 1 |
| Bernard White | Imam Al Fulani | Addict seeking Rapid Detox | 2 | 1 |
| Dean Norris | General Bowden | Bomb Specialist Clark | 2 | 1 |
| Eli Goodman | Dr. Levine | NICU Resident | 2 | 2 |
| Jeremy Ray Valdez | Petty Officer Tim Rooney | Roberto Rosales | 1 | 2 |
| Joe Nieves | Teenager #2 | Tony Dejesu | 2 | 1 |
| Kevin Fry | Cooper, Kevin | Detective Demetras | 2 | 1 |
| Louis Ferreira | Danny Dessler | Michael Mueller | 2 | 1 |
| Nadine Ellis | CTU Nurse | Mason's Wife | 2 | 1 |
| Scott Lawrence | Dr. Ben Landry | Children's Services Rep | 2 | 1 |
| Scott Paulin | Brian Jacobs | Dr. Kirsch | 2 | 1 |
| Vincent Duvall | Pilot | Father | 2 | 1 |
| Bryan Rasmussen | Agent Ed Miller | Robert Martin | 2 | 2 |
| Gary DeWitt Marshall | N.E.S.T. Tech #2 | Pete Perkins | 2 | 1 |
| Jesse D. Goins | Alan Hayes | Mr. Paige | 2 | 1 |
| José Zúñiga | Joseph Molina | Eduardo Lopez | 1 | 2 |
| Lombardo Boyar | Ramone Garcia | Morris Campbell | 2 | 1 |
| Michael O'Neill | Richard Walsh | Col. Ken Kilner | 2 | 1 |
| Wade Williams | Robert Ellis | Migraine Guy | 2 | 1 |
| Burt Bulos | FBI Agent | Lovejoy | 1 | 4 |
| Alla Korot | Suzanne Cummings | Mrs. Dupont | 1 | 1 |
| Brad Grunberg | Pool Guy | Masked Man | 1 | 1 |
| Jack Shearer | Judge Rossen | Hal Grunwald | 1 | 1 |
| Jason Padgett | Brett | Nolan (Lava Lounge Bartender) | 1 | 1 |
| Tom Irwin | John Brunner | Gabriel Milner | 1 | 1 |
| Haaz Sleiman | Heydar | Hodgkins | 2 | 1 |
| Jon Sklaroff | Ziya Dakhilov | Bible Guy, Eddie Hainey | 1 | 2 |
| Mo Gallini | Abdul, Mahnesh | Guy | 2 | 1 |
| Myndy Crist | Melissa | Valerie Page | 1 | 2 |
| Peter Onorati | FBI Agent Remick | Officer Nick Napolitano | 2 | 1 |
| Brigid Brannagh | Kathy McCartney | Jamie Hendricks | 1 | 1 |
| Connor Trinneer | Carl Gadsen | EMT | 1 | 1 |
| David Barrera | Phillips | Felix Hernandez | 1 | 1 |
| Jenni Blong | Susan Cole | Elaine Griswold | 2 | 1 |
| Michael Bryan French | Frank Simes | Dr. MacGruder | 1 | 2 |
| Nina Landey | Amanda, Eve | Vicki | 2 | 1 |
| Ray Laska | Attorney General Graves | Detective Orr | 1 | 1 |
| Roger Ranney | Infected Male Hotel Guest, Bellman | Officer Maser | 3 | 1 |
| Roman Varshavsky | Komar | Hand Guy | 1 | 1 |
| Roxanne Day | Jen Slater | Dianna | 2 | 1 |
| Sam Ayers | Agent Breeher | Mike Murphy | 2 | 1 |
| Shaun Duke | Hassan Naiyeer | Detective, Painter | 1 | 2 |
| Tim Griffin | Agent Baron | Captain John Evans | 1 | 2 |
| Tim Kelleher | Greg Merfield | U.S. Embassy Official | 1 | 1 |
| Brian Catalano | Tech Agent | Officer Cash | 2 | 1 |
| John Hawkes | Greg Penticoff | P.A. | 2 | 1 |
| Ping Wu | Su Ming | Mr. Cheung | 2 | 1 |
| Ivar Brogger | Frank Ames | Deposition Attorney | 1 | 1 |
| John Eric Bentley | Phil Holden | Larry Anderson | 1 | 1 |
| John Posey | Carl Mossman | Mr. Ramsey | 1 | 1 |
| John Pyper-Ferguson | CTU Lab Tech | Tom Coggins | 1 | 1 |
| Leonard Roberts | Guard Buchanan | Police Officer | 1 | 1 |
| Ned Schmidtke | Dr. Lee Shulman | Cal | 1 | 1 |
| Taylor Nichols | Mr. Burke | Mr. Adams | 1 | 1 |
| Tom Choi | Agent Park | Zafares | 1 | 1 |
| Carmen Mormino | Businessman, Randall Sikes | Bartender | 2 | 1 |
| Norma Maldonado | Nurse | Munoz | 1 | 2 |
| Billy Mayo | Agent Rosser | Detective Brannigan, Sheriff | 1 | 2 |
| David Gianopoulos | Sergrant Amis | John Dean / Bob Halderman | 1 | 1 |
| Eltony Williams | CTU Swat Medic | Rossen | 2 | 1 |
| Gino Montesinos | Edouardo | Officer Nunez | 2 | 1 |
| Hayley McFarland | Emily Latham | Candice | 1 | 1 |
| Jeff Kober | Conrad Haas | Stuart | 1 | 1 |
| John Rubinstein | Secretary of State | Dr. Kenner | 1 | 1 |
| Kirk B.R. Woller | Hans Meyer | Prisoner Transport Officer | 1 | 1 |
| Lamont Thompson | Manners | Paul GIlliam | 1 | 1 |
| Mandy June Turpin | Infected Female Hotel Guest | Viv Rafferty | 2 | 1 |
| Marcus Brown | Teenager #1 | Bone, Mr. Birk | 1 | 2 |
| Michael Mantell | Steve Hillenburg | Mr. Spencer | 1 | 1 |
| Paul Webster | Agent Ron | Sheriff Radford | 1 | 1 |
| Wilmer Calderon | Pedro | Mickey Stubbs | 2 | 1 |
| Taneka Johnson | Medic | Kris | 1 | 2 |
| Arjay Smith | Laurent Dubaku | Brian | 1 | 1 |
| Christopher B. Duncan | Spector | Matthew Graham | 1 | 1 |
| D.C. Douglas | USOJ Blake Simon | Ambrose | 1 | 1 |
| David Fabrizio | Strike Team Member | Michael Hanson | 1 | 1 |
| Eric Nenninger | Agent Davis | Psychotic Biting Patient | 1 | 1 |
| Evgeniy Lazarev | Nikola | Ivo Guter | 1 | 1 |
| Joe Sabatino | Captain Walleki | Pilot | 1 | 1 |
| Maz Jobrani | Marko Khatami | Henry Aquino | 1 | 1 |
| Patrick Kilpatrick | Dale Spalding | Matthew Lindermulder | 1 | 1 |
| Sandra Purpuro | Sandy | Mrs. Perrault | 1 | 1 |
| Sharon Madden | Receptionist | Risberg | 1 | 1 |
| Tomas Arana | Dave Conlon | State's Attorney Rifkin | 1 | 1 |
| Zilah Mendoza | Farah | Mrs. Sanchez | 1 | 1 |
| Austin Tichenor | Secretary of Treasury | Mr. Sumpter | 1 | 1 |
| Brett Rickaby | Sam | Vincent Hales | 1 | 1 |
| Colby French | Mike Murphy | Greg Becton | 1 | 1 |
| Esther K. Chae | Mina | Reporter Justine | 1 | 2 |
| François Chau | Koo Yin | Neuro Resident | 1 | 2 |
| Henry LeBlanc | Officer Brooks | Bartender | 1 | 1 |
| Jack Kehler | Kevin Kelly | Jail Officer | 1 | 1 |
| Jackie Debatin | Jessica Abrams | Judy | 1 | 1 |
| James MacDonald | Officer #1 | Officer Gary McWayne | 1 | 1 |
| John Cothran, Jr. | Officer #3 | Dennis Gant, Sr. | 1 | 1 |
| John Gleeson Connolly | Sergeant McLaren | Dan Udecker | 1 | 1 |
| Josh Clark | Medic | Officer McCauly | 1 | 1 |
| Keith Szarabajka | Robert Morrison | Mr. DeLuca | 1 | 1 |
| Marco Sanchez | Rafael Gutierrez | O'Connor | 1 | 1 |
| Marty Ryan | Security Guard | Brant | 1 | 2 |
| Maurice G. Smith | CTU Security Guard | Derek, Stanley Sherman | 1 | 2 |
| Tico Wells | Karris | Dr. Jennings | 1 | 1 |
| Nynno Ahli | Abbott | Security Guard | 1 | 2 |
| Carmen Argenziano | General Gratz | Howard Davis | 1 | 1 |
| Emerson Brooks | Med Tech #4 | Gonzalez | 1 | 1 |
| Eric Christian Olsen | John Mason | Travis Mitchell | 1 | 1 |
| J.D. Cullum | Bruce Margolis | Munchausen Patient | 1 | 1 |
| Jay Harik | Arabic Man | Seiger | 1 | 1 |
| Judith Scott | Dr. Kent | Mandy Smith | 1 | 1 |
| Lobo Sebastian | Prisoner Peel | Freddy Harrison | 1 | 1 |
| Michael Hyatt | Marcy | Yvonne Devilliere | 1 | 1 |
| Miguel Pérez | Ranger Mike Kramer | Santiago Escalona | 1 | 1 |
| Sam Sarpong | Officer John | Antwan | 1 | 1 |
| Scott Klace | Danny | Chris Halpern | 1 | 1 |
| Simon Templeman | Trevor Tomlinson | Gareth | 1 | 1 |
| Zina Zaflow | Melinda | Nimet Kardatay | 1 | 1 |
| John Thaddeus | Joe Prado | Keith Nelson | 1 | 1 |
| Michelle Anne Johnson | Nurse | Sarah Irving | 1 | 1 |
| Paul Vincent O'Connor | Police Chief Hendrix | tbd | 1 | 1 |
| Reggie Jordan | CTU Doctor | Street Sweeper | 1 | 1 |
| Ryun Yu | Jin | Baxter Yi | 1 | 1 |
| Shontina Vernon | Agent Zoltan | Mrs. Trager | 1 | 1 |
| Stacy Solodkin | Presidential Aide | Nancy | 1 | 1 |
| Christine Avila | Erica Farrell | Corazon | 1 | 1 |
| David O'Donnell | Police Officer | Bill | 1 | 1 |
| Ike Bram | Fareed | Eddie | 1 | 1 |
| John Rosenfeld | Kevin Aldridge | FBI Agent Robert Clayton | 1 | 1 |
| Keram Malicki-Sánchez | Larry Rogow | Rick | 1 | 1 |
| Tom McCafferty | First Secret Service Man | Worker #1 | 1 | 1 |
| Tony Perez | Douglas Newman | Mr. Mendoza | 1 | 1 |
| Bill Kalmenson | Guy In Red Shirt | Ken, Levey | 1 | 2 |
| Annie LaRussa | Jeannie Page | Sylvie | 1 | 1 |
| Deena Dill | Rita Cullens | Kristy | 1 | 1 |
| Eamon Hunt | Saunders' Man | Mrs. O'Leary's Cow | 1 | 1 |
| Eileen Galindo | Token Booth Operator | Heather Tocci | 1 | 1 |
| Jim Klock | Supervising National Guard | Tech | 1 | 1 |
| Jon Gries | Joseph Wald | Defense Attorney Marty Nesmith | 1 | 1 |
| Rick Hall | Sgt. Paulson | Detective in Larkin Case | 1 | 1 |
| Tony Lee | Deng | Fah | 1 | 1 |
| Alejandra Flores | Beatriz | Mrs. Valdez | 1 | 1 |
| Chuck Walczak | Ben | Paramedic | 1 | 1 |
| Jason Matthew Smith | Chris | Ralph Binks | 1 | 1 |
| Leesa Severyn | Agent Drake | Physical Therapist | 1 | 1 |
| Mark Bramhall | Sam | Weisner | 1 | 1 |
| Stephan DuVall | Rocco as | George Pisoni | 1 | 1 |
| Amy Benedict | Laurie Hansen | Mom | 1 | 1 |
| Ariel Felix | Anesthesiologist | Student #14 | 1 | 1 |
| Demond Robertson | CTU SWAT #1 | Paramedic Lowder | 1 | 1 |
| Fred Saldone | Driver | Stetson | 1 | 1 |
| Matt DeCaro | MTA Officer Felson | Soccer Dad | 1 | 1 |
| Peter James Smith | FBI Med Tech #2 | Mr. Shimahara | 1 | 1 |
| Sue Jin Song | Guest | Nurse Tran | 1 | 1 |
| Wiley Pickett | Simms | Impaled Man | 1 | 1 |
| Danny Arroyo | Bad Boy Dan | Dr. Reid Mooney | 1 | 1 |
| John Antonini | Commando #1 | Officer Jeff Greenberg | 1 | 1 |
| Jose Vasquez | Janitor | Nat | 1 | 1 |
| Angelo Vacco | Coffee Shop Owner | Mercy RN | 1 | 1 |
| Mercedes Colon | Kayla's Aide | Detective | 1 | 1 |
| Phyllis Lyons | Karen Pendleton | Mrs. Tubbs | 1 | 1 |
| Mary Wickliffe | Nurse | Evidence Tech | 1 | 1 |
Cast data from TVmaze, licensed CC BY-SA 4.0.