All 126 actors in both It's Always Sunny in Philadelphia and NCIS
126 actors have appeared in both It's Always Sunny in Philadelphia and NCIS, across 695 episodes. The most-credited is Andrew Friedman, Jack Kelly in It's Always Sunny in Philadelphia and George in NCIS.
| Actor | In It's Always Sunny in Philadelphia | In NCIS | Eps | Eps |
|---|---|---|---|---|
| Andrew Friedman | Jack Kelly | George | 13 | 1 |
| Gregory Scott Cummins | Luther McDonald, Donald McDonald, Bill | Kobe "Beef" Carver | 10 | 1 |
| Travis Schuldt | Ben Smith (The Soldier) | Freddy Martin, Paul Miller | 7 | 2 |
| Scott Bakula | Scott Bakula | Special Agent Dwayne Cassius "King" Pride | 1 | 4 |
| Ian Reed Kesler | Tim Murphy | Mark Daniels, Police Officer Howard Shelly | 2 | 2 |
| Lilan Bowden | Sara | Robin Knight | 1 | 3 |
| Alanna Ubach | Roxy | NSA Senior Intelligence Analyst Sofia Martinez | 1 | 2 |
| David Pressman | Delivery Guy | Dave Siebel, Lewis Dacey | 1 | 2 |
| Don Swayze | Ray | Logan Clay, Pete Walker | 1 | 2 |
| Jack Axelrod | Father O'Grady | Shmeil Pinkhas | 1 | 2 |
| Kyle Davis | Lil' Kevin | John ‘Diesel’ Stevens | 2 | 1 |
| Richard Ruccolo | Corporate Rep | Ronald Troutman | 2 | 1 |
| Robert Pine | Jack Mara | Congressman Theodore Randolph, Golfer Ben | 1 | 2 |
| Tom Bower | Pop-Pop | Sheriff Miller Thompson | 2 | 1 |
| Christine Woods | Mandy | Rebecca Jennings | 1 | 1 |
| D'Anthony Palms | David | Ticket Taker | 1 | 1 |
| David Marciano | Detective Larson | Bartender | 1 | 1 |
| Dean Cameron | Dave Drisko | Building Owner | 1 | 1 |
| Erin Matthews | Abey | Deputy Attorney General Mara Reeves | 1 | 1 |
| J.D. Walsh | Doctor | Leonard Finnik | 1 | 1 |
| Jason Manuel Olazábal | Worker | Todd Mercer | 1 | 1 |
| Jessica Collins | Jackie Denardo | Judy Ford | 3 | 1 |
| Kari Coleman | Margie | Maggie Scott | 1 | 1 |
| Lisa LoCicero | Philadelphia Soul Executive | Elena Devol | 1 | 1 |
| Marshall Allman | Bezzy | Donnie James Bailey | 1 | 1 |
| René Auberjonois | Dr. Larry Meyers | Dr. Felix Blackwell | 1 | 1 |
| Seth Coltan | Man | Deputy Allen Smedley | 1 | 1 |
| Shaw Jones | Zoo Worker | Navy Commander George Campbell | 1 | 1 |
| Tyler Tomás Perez | Darren | Navy P.O. First Class Sam Vega | 1 | 1 |
| William Morgan Sheppard | Father Cullen | Marcin Jerek | 1 | 1 |
| Jack McGee | Detective Lance Girard | Det. Floyd, Richard "Rick" Jordan | 1 | 2 |
| Jean St. James | Customer | Marilyn Davis | 1 | 2 |
| Marcuis Harris | Pimp (Pepper Jack) | Chris Jenkins | 2 | 1 |
| Noah Bean | Art Sloan | DOD Chief David Barbado | 1 | 2 |
| Peter MacKenzie | Doctor | Jack Murdoch | 2 | 1 |
| Robert Adamson | Trey | Senior Cadet Lucas Craig | 2 | 1 |
| Audrey Wasilewski | Nurse | Shirley Wilkes | 1 | 1 |
| Carter MacIntyre | Male Model, Mike | Benjamin "Benny" Sitano, Junior | 2 | 1 |
| Dominic Burgess | Psycho Pete | Leonard | 1 | 1 |
| Emily Chang | Dr. Ling | Phyllis Moss | 1 | 1 |
| Geoff Pierson | Warden | Roy Carver | 1 | 1 |
| Gerald Downey | Bill Larkin | Navy Cmdr. Ray Trapp | 1 | 1 |
| Hugh Holub | Colin Clark (Judge) | Superintendant | 1 | 1 |
| Jack Guzman | Young Veteran | Wade | 1 | 1 |
| Jackie Tohn | Asriel | Counselor Celia Ross | 1 | 1 |
| John Rosenfeld | Morris | FBI Agent Charles | 1 | 2 |
| Josh Stamberg | Ari Frenkel | Marine Major Ike Varnai | 1 | 1 |
| Judith Drake | Lil' Kevin's Mom | Delores | 1 | 1 |
| Laura P. Vega | Mother Juarez | Maria | 1 | 1 |
| Lindsey McKeon | Rebecca Keane | Taylor Matthews | 1 | 1 |
| Rizwan Manji | Mehar | Dr. Pandy | 1 | 1 |
| Robert Wu | Man | Klugman | 1 | 1 |
| Suzanne Quast | Tabitha | Liz Allen | 1 | 1 |
| Timothy Davis-Reed | Brandon | Edison Rawls | 1 | 1 |
| Will Harris | Security Guard | Murray Hines | 1 | 2 |
| Winston Story | Nurse | Manny | 1 | 1 |
| Cheryl Texiera | Jane Ponderosa | Jezebel Poppins | 2 | 1 |
| Sasha Roiz | Adriano Calvanese | NCIS Agent Rick Hall | 2 | 1 |
| Adam J. Harrington | Gym Manager | Coast Guard Commander Sam Hendrix | 1 | 1 |
| Aja Evans | Gloria | Taylor | 1 | 1 |
| Annalisa Cochrane | Birthday Girl | Lisa Swenson | 1 | 1 |
| Burl Moseley | Maxwell | Nurse | 1 | 1 |
| Christine Horn | Cop | Doctor Felicia Serena | 1 | 1 |
| Cleo King | Nurse Wendy | Della Robinson | 1 | 1 |
| Jeremy Denzlinger | Police Officer | NCHP Colonel Bill Timmons | 1 | 1 |
| Jim Lau | Asian Worker | Old Vendor | 1 | 1 |
| Julia Cho | Dot Com Girl | Ginger Uwanawich | 1 | 1 |
| Karl T. Wright | Scott | John Hicks | 1 | 1 |
| Kristen O'Meara | Beth | Lydia Smith | 1 | 1 |
| Mercedes Colon | Council Woman | Gina | 1 | 1 |
| Michael Marc Friedman | Young Cop | Gunnery Sgt. Joseph Wilkes | 1 | 1 |
| Nick Toren | Salesman | Dwight's Father | 1 | 1 |
| P.J. Byrne | Tad | Ross Logan | 1 | 1 |
| Peter Asle Holden | Union Delegate | Vector Control Worker | 1 | 1 |
| Robert Blanche | Detective Jones | Brett Willis | 1 | 1 |
| Sam Witwer | Muscular Guy | S Sgt. Rafael | 1 | 1 |
| Spencer Daniels | Tommy | Brett Murphy | 1 | 1 |
| Van Epperson | Boss | Pop | 1 | 1 |
| Zack Ward | Davy Mara | Police Officer Billy Krieg | 1 | 1 |
| Carlin James | Max | Navy Seaman Felix Pittorino | 1 | 1 |
| Casey Sander | Group Leader | Ed Gantry | 1 | 1 |
| Cory Blevins | Benjamin's Dad | Father | 1 | 1 |
| Courtney Gains | Roach | Gary Silverstin | 1 | 1 |
| Eddie Shin | Moderator Mike | CGIS Special Agent Kyle Omagi | 1 | 1 |
| Gary Kraus | Dad | Chuck Parnell | 1 | 1 |
| Jamie Sorrentini | Slutty Woman | Francine "Frankie" Mancuso | 1 | 1 |
| Jeremy Ratchford | Detective | Baltimore Police Detective Ramsey Malone | 1 | 1 |
| Keir O'Donnell | Jan | Ramsey Boone | 1 | 1 |
| Marc Anthony Samuel | Raisin #1 | Marine Private First Class James Hall | 1 | 2 |
| Matt Corboy | Airport Security | Petty Officer Lance Tolliver | 1 | 1 |
| Matthew Jones | Customer #1 | Navy Commander Rick Odwalla | 1 | 1 |
| Mike Beaver | Man-Office Worker | Larry West | 1 | 1 |
| Paloma Esparza Rabinov | Britney | Sober Sally | 1 | 1 |
| Phil Abrams | Doctor | Hotel Manager | 1 | 1 |
| Roy Jackson | Policeman | Bartender | 1 | 1 |
| Scott Beehner | Doctor | Milton | 1 | 1 |
| Steve Tom | Jameson Taft | George Ashley Green | 1 | 1 |
| Stuart McLean | Another Patron | Malcolm Turro | 1 | 1 |
| William C. Mitchell | Bobby Barrett | War Veteran #1 | 1 | 1 |
| William Duffy | Hedge Fund Guy | Head of Security Harris Cobb | 1 | 1 |
| Andrew Thacher | Detective | West Virginia State Trooper Sergeant Paul Westgard | 1 | 1 |
| Anthony Hill | Black Mac | Navy Petty Officer Third Class John Blaney "JB" Hicks | 1 | 1 |
| Barry Livingston | Third Executive | Bartholomew Lemming | 1 | 1 |
| Brad Lee Wind | Angry Dad | Metro P.D. Sergeant John Dunn | 1 | 1 |
| Brady Smith | Tony | David Cross | 1 | 1 |
| Devan Long | Gym Worker | NCIS Lead Evidence Custodian Terry Keller | 1 | 1 |
| Iman Crosson | Patrick | Navy Lieutenant Elliot Greene / Man | 1 | 1 |
| Lauren McKnight | Anna | Miss Sharpe aka Assassin | 1 | 1 |
| Patrick Hume | Edgar | Jerry | 1 | 1 |
| Paul Bartholomew | Psychic John | Spencer Dodd | 1 | 1 |
| Tacey Adams | Psych Professor | Grandma Avatar | 1 | 1 |
| Wendy Braun | Lauren | Cindy Sanchez | 1 | 1 |
| Will Beinbrink | 1st Man at Art Show | Oliver Lambert | 1 | 1 |
| Phil Idrissi | Salesman | Big Lou | 1 | 1 |
| Tom Virtue | Rink Official | Frank Satner | 1 | 1 |
| Treisa Gary | Teacher | Hannah | 1 | 1 |
| Brandon Molale | Big Eric | Army CID Special Agent Jack Reynolds | 1 | 1 |
| George Tsai | Patriots' Trainer | Nurse Keith Johnson | 1 | 1 |
| Gichi Gamba | Boko Haram Leader | Bodyguard | 1 | 1 |
| Harvey J. Alperin | Professor 2 | Henry Mantell | 1 | 1 |
| Kirk Bovill | Colonel Wahington | Richard Sims | 1 | 1 |
| Robert Craighead | Gabe | DEA Agent Simon Lewis | 1 | 1 |
| Brian Fitzpatrick | Eddie | Willis Hirst | 1 | 1 |
| Karly Rothenberg | Another Mom | Female Passerby | 1 | 1 |
| Reatha Grey | Ruth | Marion | 1 | 1 |
| Robbie Tucker | Young Charlie | Smartass Tagger | 1 | 1 |
← It's Always Sunny in Philadelphia × NCIS
Cast data from TVmaze, licensed CC BY-SA 4.0.