| Name | Character | Episodes |
|---|---|---|
| Harry Shum Jr. | Magnus Bane | 55 |
| Katherine McNamara | Clary Fray | 55 |
| Dominic Sherwood | Jace Wayland | 55 |
| Isaiah Mustafa | Luke Garroway | 55 |
| Emeraude Toubia | Izzy Lightwood | 55 |
| Matthew Daddario | Alec Lightwood | 55 |
| Alberto Rosende | Simon Lewis | 55 |
| Nicola Correia Damude | Maryse Lightwood | 55 |
| Alisha Wainwright | Maia Roberts | 28 |
| Anna Hopkins | Lilith | 22 |
| Alan van Sprang | Valentine Morgenstern | 16 |
| David Castro | Raphael Santiago | 15 |
| Maxim Roy | Jocelyn Fray | 14 |
| Jon Cor | Hodge Starkweather | 10 |
| Will Tudor | Sebastian Verlac | 9 |
| Joel Labelle | Alaric | 9 |
| Christina Cox | Elaine Lewis | 8 |
| Stephanie Bennett | Lydia Branwell | 8 |
| Nick Sagar | Victor Aldertree | 8 |
| Kaitlyn Leeb | Camille Belcourt | 7 |
| Steve Byers | Underhill | 6 |
| Paulino Nunes | Robert Lightwood | 6 |
| Kimberly-Sue Murray | Seelie Queen Amara | 6 |
| Jade Hassouné | Meliorn | 6 |
| Shailene Garnett | Maureen | 5 |
| Chai Hansen | Jordan Kyle | 4 |
| Lisa Berry | Cleophas Garroway | 4 |
| Sydney Ozerov-Meyer | Helen Blackthorn | 4 |
| Raymond Ablack | Raj | 4 |
| Lola Flanery | Seelie Queen | 3 |
| Lisa Marcos | Captain Susanna Vargas | 3 |
| Jack Fulton | Maxwell "Max" Lightwood | 3 |
| Kyana Teresa | Lanaia | 3 |
| Stephen R. Hart | Brother Jeremiah | 3 |
| Joanne Jansen | Gretel | 3 |
| Curtis Morgan | Pangborn | 3 |
| Sarah Hyland | Seelie Queen | 2 |
| Holly Deveaux | Rebecca Lewis | 2 |
| Adam J. Harrington | Michael Wayland | 2 |
| Tomaso Sanelli | Young Jace | 2 |
| Stephanie Belding | Dr. Iris Rouse | 2 |
| Nykeem Provo | Young Luke Garroway | 2 |
| Michael Cram | Ned Fisk | 2 |
| Susanna Fournier | Young Jocelyn | 2 |
| Stephen Huszar | Brad | 1 |
| Jessica Matten | Maria | 1 |
| Mimi Kuzyk | Imogen Herondale | 1 |
| Lisa Berry | Cleophas Garroway (uncredited) | 1 |
| McG | Himself | 1 |
| Jenny Raven | Leigh | 1 |
| Alexander Eling | Teen Alec (as Alex Eling) | 1 |
| Owen Roth | Young Valentine | 1 |
| Ed Decter | Himself | 1 |
| Farah Merani | Sister Magdalenda | 1 |
| Vicki Kim | Anna | 1 |
| Jesse Camacho | Leo | 1 |
| Romy Weltman | Teen Isabelle Lightwood | 1 |
| Michelle Argyris | Kaelie | 1 |