 | Jacob Tremblay als Orion (voice) |
 | Paul Walter Hauser als Dark (voice) |
 | Angela Bassett als Sweet Dreams (voice) |
 | Colin Hanks als Adult Orion (voice) |
 | Natasia Demetriou als Sleep (voice) |
 | Golda Rosheuvel als Unexplained Noises (voice) |
 | Nat Faxon als Insomnia (voice) |
 | Aparna Nancherla als Quiet (voice) |
 | Ike Barinholtz als Light (voice) |
 | Carla Gugino als Orion's Mom (voice) |
 | Matt Dellapina als Orion's Dad (voice) |
 | Nick Kishiyama als Tycho (voice) |
 | Mia Akemi Brown als Hypatia (voice) |
 | Shannon Chan-Kent als Adult Hypatia (voice) |
 | Jack Fisher als Richie Panici (voice) |
 | Werner Herzog als Narrator (voice) |
 | Sky Alexis als Lisa (voice) |
 | Hira Ambrosino als Woman at the Drive-In (voice) |
 | Yoshi Ando als Man at the Drive-In (voice) |
| Larisa Asuaje als Mrs. Spinoza (voice) |
 | Sean Charmatz als Irene's Boss / Cucumber Dentist / Soda / Insomnia Guy 1 (voice) |
 | Walt Dohrn als Stray Cat / Insomnia Guy 2 (voice) |
 | Ren Hanami als Adult Sally (voice) |
 | Amy Hill als Irene (voice) |
| Alyssa Lee als Irene's Daughter / Insomnia Girl (voice) |
| Noah McCown als Scared Child (voice) |
| Shino Nakamichi als Sally (voice) |
| Aliki Theofilopoulos als Irene's Coworker / Mom / Juice Box / Insomnia Teacher (voice) |
 | Toru Uchikado als Insomnia Man (voice) |
| Charlie Kaufman | Writer |
| Emma Yarlett | Book |
| Sean Charmatz | Director |
| Peter McCown | Producer |
| Walt Dohrn | Executive Producer |
| Bonnie Arnold | Executive Producer |
| Tim Lamb | Production Designer |
| Christine Bian | Art Direction |
| Adam Rosette | Head of Story |
| Hans Dastrup | Head of Animation |
| Tim Nielsen | Sound Designer |
| Tim Nielsen | Supervising Sound Editor |
| Tim Nielsen | Sound Re-Recording Mixer |
| Nik Ranieri | Supervising Animator |
| Shawn Krause | Supervising Animator |
| Steve Slanec | Supervising Sound Editor |
| Brandon Proctor | Sound Re-Recording Mixer |
| Nathan Nance | Sound Re-Recording Mixer |
| Kevin Lax | Original Music Composer |
| Robert Lydecker | Original Music Composer |
| Kevin Sukho Lee | Editor |
| Leah Artwick | Story Artist |
| Alex Avagimian | Story Artist |
| Joe Bernados | Story Artist |
| Lyle Nagy | Story Artist |
| Kent Osborne | Story Artist |
| Jordan Rosato | Story Artist |
| Janie Kahan | Production Coordinator |
| Michael Pedraza | Associate Editor |
| Dylan Stayman | Assistant Editor |
| Keith Bodmer | Assistant Editor |
| Eric Hendricks | Assistant Editor |
| Claire Liu | Production Coordinator |
| Timothy Lamb | Character Designer |
| Jesse Aclin | Character Designer |
| Elaine Choi | Character Designer |
| Ryan Matias | Character Designer |
| Joe Pitt | Character Designer |
| Guillaume Fesquet | Visual Development |
| Emily Tetri | Visual Development |
| Miho Tomimasu | Visual Development |
| Kevin Turcotte | Matte Painter |
| Mallory Quagliato | Production Coordinator |
| Brittany Ramirez | Production Assistant |
| Carla Lutz | Animation Supervisor |
| Julien Bocabeille | Animation |
| Greg Sharp | Animation |
| Emily Tetri | Animation |
| Meghan Noyes | Production Coordinator |
| Amanda Lennes | Production Assistant |
| Ashley Laidlaw | Line Producer |
| Kyle Hancher | Production Manager |
| Robert Dudban | Finance |
| Mila Montano | Production Accountant |
| Ryan Munk | CG Supervisor |
| Ernest Chan | Animation Supervisor |
| Brent Hutchins | Line Producer |
| Candice Ray | Production Manager |
| Kristin Risinger | Production Manager |
| Zachary Joel Johnson | Production Coordinator |
| Emily Ryker | Production Coordinator |
| Brent Tyler | VFX Supervisor |
| Steven Tarin | Modelling Supervisor |
| Belal Ballout | Rigging Supervisor |
| Natalie Jimenez | Generalist |
| Ross Gibson | Effects Supervisor |
| David Lee-DuVoisin | Lighting Supervisor |
| David Lee-DuVoisin | Compositing Supervisor |
| Andrea Miloro | Executive Producer |
| Adrianna A.J. Cohen | Executive Producer |
| Russell Tracy Jr | Executive Producer |
| Natalia Lasota | Line Producer |
| Murali Chinnappa | Line Producer |
| Ravi Kiran Nunna | Producer |
| Charan Paruchuri | Production Manager |
| Kartheek Dugyala | Production Manager |
| Guru Gnasasambandan | Production Manager |
| Rahul Gattu | Production Coordinator |
| Sandra Geiben | Production Coordinator |
| Swati Pattnaik | Production Coordinator |
| Bandana Panigrahi | Production Assistant |
| Masool Afreen | Production Assistant |
| Neelam Kishan | Production Assistant |
| Manoj Menon | Creative Director |
| Francis Rajeev A. | Modelling Supervisor |
| Rakesh Acharya B. | Modelling Supervisor |
| Robin Bharat | Modeling |
| Samir Rout | Modeling |
| Suraj Kumar Raut | Modeling |
| Dilip Kumar Y Bhandi | Rigging Supervisor |
| Deepak Ganguly | Animation Supervisor |
| Kaustav Chakravarty | Animation Supervisor |
| Rubul Das | Animation Supervisor |
| Deepanita Manna | Lead Animator |
| Shiladitya Gupta | Lead Animator |
| Vedanth Rajan | Lead Animator |
| Bruno Etchepare | Animation |
| Gopi Gudelli | Animation |
| Arnap Sarkar | Animation |
| Dhiraj Prasad | Visual Effects Supervisor |
| Kannan Logiah | Visual Effects Supervisor |
| Sai Kumar Barnala | Visual Effects Supervisor |
| Kunal Gupta | Visual Effects |
| Shahwaz Ansari | Visual Effects |
| Yugesh Kampalli | Visual Effects |
| Vinodh Prasanna | Lighting Supervisor |
| Parthiban Sundaram | Lighting Supervisor |
| Sabyasachi Chatterjee | Lighting Supervisor |
| Vinodh Prasanna | Compositing Supervisor |
| Parthiban Sundaram | Compositing Supervisor |
| Sabyasachi Chatterjee | Compositing Supervisor |
| Lalit Karel | Lighting Artist |
| Bhrat Kabra | Lighting Artist |
| Chintu Kumar | Lighting Artist |
| Lalit Karel | Compositing Artist |
| Bhrat Kabra | Compositing Artist |
| Chintu Kumar | Compositing Artist |
| Babulu P George | CG Supervisor |
| Naresh Gunda | CG Supervisor |
| Jessey Drake | Sound Designer |
| Jeff Halbert | Sound Designer |
| Marc Schmidt | Sound Designer |
| Laria Martinez-Deleon | Sound Effects |
| Matthew Festle | Sound Effects |
| Cat Gensler | Sound Effects |
| Grace Stenland | Sound Effects |
| Roberto D. Alegria | Foley Mixer |
| Vincent Deng | Foley Artist |
| Laura Macias | Foley Artist |
| Jason Oliver | Dialogue Editor |
| Patricia Burgos | Post Production Supervisor |
| Ian Michael Hurley | Online Editor |
| Emily Horton | Post Production Coordinator |
| D.J. Lynch | Sound Re-Recording Mixer |
| Rob McIntyre | Supervising Sound Editor |
| Ania O'Hare | Casting |
| Katie Galvan | Casting |
| Meghan Noyes | In Memory Of |
| Noelle McCown | In Memory Of |
| Kristin Sando | Associate Producer |
| Timothy Lamb | Production Designer |
| M. Scott McKee | Visual Effects Supervisor |
| Killian Gray | Production Manager |
| Aubin Schuler | Production Supervisor |
| Matthew Festle | Sound Editor |
| Dipika Das | Animation Director |
| Lloyd Taylor | Additional Writing |
| Brandon Sawyer | Additional Writing |
| Vivian Aguiar-Buff | Music |
| Matt Manna | Music |
| Alexandra Nickson | Music |
| Matthew Bordenave | Story Artist |
| Austen Aevery Huens | Story Artist |
| Kaan Kalyon | Story Artist |
| Jon Magram | Story Artist |
| Gaëlle Beerens | Story Artist |
| Tom Caulfield | Story Artist |
| Eric Elrod | Story Artist |
| Nathan Gelgud | Story Artist |
| James P. Gibson | Story Artist |
| Zesung Kang | Story Artist |
| Hanna Kim | Story Artist |
| Johane Matte | Story Artist |
| Catherine Yuh Rader | Story Artist |
| Justin Ridge | Story Artist |
| Jessica Kaori Stanley | Story Artist |
| Bob Flynn | Character Designer |
| Nico Marlet | Character Designer |
| John-Paul Balmet | Visual Development |
| Pablo J. Rivera | Visual Development |
| Andy Schuhler | Visual Development |
| Chris Sears | Visual Development |
| Elaine Wengi Wu | Visual Development |
| Katy Wu | Visual Development |
| Lauren Zurcher | Visual Development |
| Alfonso Blaas Nacle | Visual Development |
| Marcos Elizalde | Visual Development |
| Gijsbrecht Evens | Visual Development |
| Kirsten Kawamura | Visual Development |
| Leo Matsuda | Visual Development |
| Ruben Perez | Visual Development |
| Ritchie Sacilioc | Visual Development |
| Pedro Della Conti | Other |
| Dor Shamir | Other |
| Abhishek Mukherjee | Animation |
| Anand Avira | Animation |
| Aniket Suresh Marathe | Animation |
| Anuska Mondal | Animation |
| Anuska Poddar | Animation |
| Aravind Kumar Kommoju | Animation |
| Anarb Halder | Animation |
| Anarp Sarkar | Animation |
| Atanu Patra | Animation |
