Editing Third Watch (section)

===Recurring cast===
These cast members are listed by the season in which they were introduced:

{| class="wikitable"
|-
! Actor || Character || Seasons as recurring cast || Notes
|-
|[[Derek Kelly]] || FDNY Firefighter Derek "DK" Kitson || 1–6 || Real-life FDNY firefighter; real-life husband of Molly Price
|-
|[[Bill Walsh (actor)|Bill Walsh]] || FDNY Firefighter/Lieutenant [[Billy Walsh (Third Watch)|William "Billy" Walsh]] || 1–6 || Real-life FDNY firefighter
|-
|[[Patti D'Arbanville]] || Rose Boscorelli || 1–6 || Bosco's mother
|-
|Jeremy Bergman || Charles "Charlie" Yokas || 1–4 || Faith and Fred's youngest child
|-
|[[Lonette McKee]] || Maggie Davis || 1–4 || Ty's mother
|-
|[[Monica Trombetta]] || Dana Murphy || 1–2 || ER Nurse
|-
|[[James Rebhorn]] || NYPD Captain "Stick" Elchisak || 1–3 || NYPD Captain of 55th Precinct
|-
|P.J. Morrison || Emily Yokas || 1–3 || First actress to portray character
|-
|Kristopher Scott Fiedell || Joseph "Joey" Doherty || 1–3 || Kim and Jimmy's son
|-
|[[Eva LaRue]] || NYPD Officer Brooke Doherty || 1–2 || Jimmy's second wife
|-
|[[Lisa Vidal]] || Dr. Sarah Morales || 1–2 || Attending at Mercy Hospital; Doc's love interest
|-
|[[Wendell Pierce]] || NYPD Officer Conrad "Candyman" Jones || 1 || Cop with long and spotty history partnered with Davis' father
|-
|[[Nick Chinlund]] || NYPD Detective Tancredi || 1 ||
|-
|[[Ernest Mingione]] || NYPD Lieutenant Kowalski || 1 ||
|-
|[[Peter Vack]] || "The Rod Rodney" || 1 ||
|-
|[[Jon Seda]] || Mateo "Matty" Caffey || 1–2 || Bobby's ex-con brother
|-
|Saundra McClain || Nurse Mary Proctor || 2–6 || Primary nurse at Mercy
|-
|[[John Michael Bolger]] || FDNY Lieutenant Johnson || 2–4 ||
|-
|[[Savannah Haske]] || Tatiana Deschenko || 2–4 || Wife of Sully
|-
|Nick Sandow || FDNY Firefighter Joseph "Joe" Lombardo III || 2 ||
|-
|Carol Woods || NYPD Lieutenant Rice || 2 ||
|-
|[[Anne Twomey (actor)|Anne Twomey]] || Catherine Zambrano || 2 || Mother of Kim
|-
|[[Joe Lisi]] || NYPD Lieutenant [[Bob Swersky|Robert "Bob" Swersky]] || 3–6 ||
|-
|[[Sterling K. Brown]] || NYPD Officer Edward Dade || 3–5 ||
|-
|[[Charlie Day]] || Michael "Mikey" Boscorelli || 3–5 || Brother of Bosco
|-
|[[Brad Beyer]] || NYPD Sergeant Jason Christopher || 2–3 ||
|-
|[[Charlie McWade]] || NYPD Officer Steven Gusler || 3 || A squeamish new officer training under Yokas and Bosco
|-
|[[Darien Sills-Evans]] || Dr. Fields || 4–6 || Attending at Mercy
|-
|[[James Remar]] || NYPD Detective Madjanski || 4 ||
|-
|Yvonne Jung || FDNY Paramedic Holly Levine || 5–6 || Love interest of Carlos, real-life wife of Anthony Ruivivar
|-
|[[Joe Badalucco]] || NYPD Detective [[Jelly Grimaldi|"Jelly" Grimaldi]] || 5–6 || Yokas' partner once she was promoted to detective
|-
|[[Charles Haid]] || NYPD IAB Captain Cathal "CT" Finney || 6 || Corrupt; father of Brendan
|-
|[[Manny Pérez]] || NYPD Officer Manny Santiago || 6 || Partner to Cruz
|-
|[[Aidan Quinn]] || NYPD Lieutenant John Miller || 6 || Partner and eventual love interest to Yokas
|-
|[[Jason Shaw]] || FDNY Firefighter Stu "Lotta Zs" Szczelaszczyk || 6 ||
|}