She gained fame for playing the title role of a waitress at a roadside diner in the CBS sitcom Alice (1976–1985), a role for which she was nominated for the Primetime Emmy Award for Outstanding Lead Actress in a Comedy Series and won two consecutive Golden Globe Awards for Best Actress in a Television Series – Musical or Comedy.

She was Tony-nominated for her roles in Last of the Red Hot Lovers (1970), The Diary of Anne Frank (1998), The Tale of the Allergist's Wife (2001), Collected Stories (2010), and The Lyons (2012).

[10] In 1967, Lavin made an appearance as Gloria Thorpe in a television version of the baseball musical Damn Yankees with Phil Silvers.

After various guest appearances on episodic television series such as The Nurses, Rhoda, Harry O, and Kaz, Lavin landed a recurring role as Detective Janice Wentworth on Barney Miller during the first and second seasons (1975–1976).

Lavin performed the series' theme song, "There's a New Girl in Town," which was written by David Shire and Alan and Marilyn Bergman and was updated for each of the first six seasons.

[15] Lavin also made numerous television appearances outside of Alice, including hosting her own holiday special for CBS, Linda in Wonderland (1980).

[17] She made numerous television guest appearances, including roles on The Muppet Show (1979), Law & Order: Criminal Intent, The O.C., Touched by an Angel (1999), and HBO's The Sopranos (2002).

She also appeared in many telefilms between 1967 and 1998, including: Damn Yankees!, Sadbird, The Morning After, Jerry, Like Mom, Like Me, The $5.20 an Hour Dream, Another Woman's Child, Maricela, Lena: My 100 Children, Whitewash, A Dream is a Wish Your Heart Makes: The Annette Funicello Story, Stolen Memories: Secrets from the Rose Garden, For the Future: The Irvine Fertility Scandal, The Ring, and Best Friends for Life.

Lavin produced and starred in A Matter of Life and Death, the 1981 telefilm based on the work of nurse thanatologist Joy Ufema.

[19] Her other feature film appearances include See You in the Morning, starring Jeff Bridges; Alain Resnais's I Want to Go Home, opposite Gérard Depardieu (both 1989); and The Back-up Plan (2010).

[20] Lavin also provided the voice of the Mother Vulture in the animated series Courage the Cowardly Dog for the episode "Watch The Birdies".

The Los Angeles Times interviewer noted: "A highlight of the show is the wonderful chemistry between Lavin and Hayes, who exchange repartee and quips with breezy ease.

Lavin caught up with Portland Magazine in its Winterguide 2018 issue about her return to CBS stating: Like Alice, 9JKL deals with family relationships–except it's a more sophisticated and edgier show.

[27][28][29] Lavin appeared in the CBS comedy B Positive, which aired from 2020 to 2022, in a recurring role as Norma, one of the senior citizens at a local retirement home.

[39] In his New York Times review of John Guare's two one-act plays, Cop-Out (1969), Clive Barnes wrote: "Miss Lavin...carries versatility almost to the point of paranoia, and camps up a storm.

"[40] Lavin also appeared in numerous Off-Broadway productions, including the revue Wet Paint (1965),[41] the musical The Mad Show (1966)[42] (in which she introduced the cabaret standard "The Boy From...", written by Stephen Sondheim and Mary Rodgers),[43] and Little Murders (1969).

Clive Barnes, in his review for The New York Times, wrote: "Linda Lavin, eyebrows, [sic] flaunting like telegraphed messages, mouth twitching and pouting, voice as dry as thunder and with a cough like electric static, is beautiful as Elaine, the sex cat feeling coolly kittenish and looking for a safe tin roof.

In his review in The New York Times, Frank Rich wrote: "One only wishes that Ms. Lavin, whose touching performance is of the same high integrity as the writing, could stay in the role forever.

"[53] Theatre critic Charles McNulty wrote of her performance that it "is widely considered one of the most memorable in contemporary Broadway history, winning not just awards but praise approaching the level of myth.

The theater critic Gordon Rogoff, extolling 'the power available only to an actor at the height of her own command of detail,' went so far as to describe Lavin's portrayal as 'one of those textbook lessons in great acting...' "[54] She then starred on Broadway in Gypsy as Mama Rose Hovick, replacing Tyne Daly in July 1990.

[56] Her subsequent Broadway roles included The Sisters Rosensweig, as a replacement Gorgeous Teitelbaum starting in September 1993[57] and Mrs. Van Daan in The Diary of Anne Frank (1997–1998), opposite Natalie Portman, for which she garnered a Tony nomination as Featured Actress in a Play.

Ben Brantley, in his review for The New York Times wrote: "And it's an unconditional treat to witness an actress like Ms. Lavin tuned so precisely into the writer's wavelength that script and performance become a marriage of true minds.

[73] In January 2017, Lavin appeared in New York City Opera's production of Leonard Bernstein's Candide at the Rose Theatre at Lincoln Center in the role of The Old Lady.

[75][76] Writing in The New York Times, critic Ben Brantley called her performance of the song "deliciously undersold," and noted that she had introduced it 54 years earlier.