Ford initially worked as a model for the Montgomery Ward catalog when she was 15 years old. Her face became famous in the Elizabeth Arden 1941 advertising campaign for Victory Red lipstick, which featured a Philippe Halsman photo showing her face against the American flag. She had some success as an Actress on Broadway from 1949, appearing in such productions as the musical Say Darling and Nobody Loves an Albatross. She also played Miss Forsythe in the first production of Death of a Salesman.

She began her television career in 1950, performing in live television dramas on Studio One, Armstrong Circle Theatre, Goodyear Television Playhouse, and other acclaimed series. As a Warner Brothers contract player, she had her most famous role as Sandra Dee's heartless mother in A Summer Place (1959), in which her abused husband Richard Egan had a memorable scene telling her off for her outdated prejudices, and Ford arranges for Dee to be tested for her virginity. Another shocking scene had Ford slapping Dee so hard that she fell into a Christmas tree which toppled over on her. In Rome Adventure (1962) she played Daisy Bronson, owner of a bookstore in Rome, opposite Suzanne Pleshette and Troy Donahue, being kinder to him than she had been in A Summer Place. In House of Women, she played an aggressive but ultimately sympathetic female prisoner who gets into a catfight with prison matron Jeanne Cooper. She played the tough-as-nails nurse alongside Joan Crawford in The Caretakers (1963). She also had a memorable walk-on playing a flirtatious but bored society matron who makes a play for Warren Beatty in All Fall Down.

In 1954 she made her soap opera debut as Lynn Sherwood on Woman With A Past on CBS. On Search for Tomorrow, Ford was Rose Peterson, an employee of the mob who was hired to discredit leading character Joanne Tate. Her on-screen brother was played by Don Knotts. The role of Rose was also played by Lee Grant and Nita Talbot.

Ford's assertive style made her a favorite of TV casting Directors. She made three memorable appearances on Perry Mason, including the role of a woman with split personality in the 1958 episode "The Case of the Deadly Double", and as Frances Walden in "The Case of the Potted Planter" (1963) and defendant Sylvia Thompson in "The Case of the Shifty Shoebox" (also 1963). In 1960, she played heartless Connie Walworth ("You haven't got the flair, dear ...") for Director Mitchell Leisen in the "Worse Than Murder" episode of Thriller. She was often featured in episodes of Kraft Television Theater, Appointment with Adventure, State Trooper, Bat Masterson, The Phil Silvers Show, Have Gun – Will Travel, Rawhide, Wanted: Dead or Alive, Tombstone Territory (episode "Silver Killers"), Gunsmoke, Alfred Hitchcock Presents, Target: The Corruptors!, and in The Twilight Zone episode "Uncle Simon". She also appeared on the NBC interview program Here's Hollywood. One of her Perry Mason episodes is on display as part of the introduction for jurors who serve in New York's Criminal Courts.

On The Edge of Night, Ford played the murderous theatre owner Eve Morris. Following that stint, she joined Another World, where from 1967 to 1992, she played the role of Ada Davis, the strong-willed mother of Rachel (Robin Strasser and later Victoria Wyndham). While her mother character was a total contrast to her role of Helen in A Summer Place, she was brutally tough and honest, yet supportive and loving and became a mentor to many of Bay City's young characters who were no relation to her. Her first line upon entering the room was responding to brother Sam Lucas's inquiry, "Ada, is that you?" with the bark of "No, it's Princess Grace!" Over the years, Ada was widowed three times and worked in a variety of professions, from hairdressing to clerk in the police station to finally a restaurant owner. In 1975, the middle-aged Ada gave birth to a daughter, Nancy. When she left the show in 1992 due to declining health, her character was said to be out of town visiting Nancy. When Ford died, the character of Ada also died off-screen and the show had a tribute to her that featured many vintage flashbacks.

Ford died in New York Hospital in Manhattan on February 26, 1993, from cancer, aged 69. She had no survivors.

At the time Ford left the program, she was the longest-running performer on Another World. By the time the series ended in 1999, Ford's television daughter Victoria Wyndham was the longest-running performer on the show.