Goodwin was born in Memphis, Tennessee. Her mother, Linda (née Kantor), is a former educator and "stay-at-home mom" who later worked for FedEx and Apple. Her father, Tim Goodwin, formerly owned and operated a recording studio. Goodwin changed her name from "Jennifer" to "Ginnifer" to distinguish her name, and to assist in pronunciation of her name in her regional dialect. Her younger sister, Melissa Goodwin, is a stop motion animator on shows such as Robot Chicken, on which Ginnifer has also appeared as voice talent.
Her father is Christian with Welsh ancestry, and her mother is Jewish. Goodwin was raised attending synagogue on Saturdays and Unitarian church on Sundays. She was both baptized and had a bat mitzvah service. In her youth, Goodwin was affiliated with the North American Federation of Temple Youth, and was active in BBYO at the Jewish Community Center in Memphis. She went to school at St. Mary's Episcopal School in Memphis, Tennessee. She then graduated from Lausanne Collegiate School in 1996, then attended Hanover College (majoring in Theater) for one year before moving on to earn her Bachelor of Fine Arts from Boston University. While a student at BU, she performed in numerous student short films, as well as several college and local stage productions. Goodwin was given the "Excellence in Acting: Professional Promise Award" by the Bette Davis Foundation, and graduated with honors. After her time at Boston University, she studied in England at Stratford Upon-Avon's Shakespeare Institute, in conjunction with the Royal Shakespeare Company. The following year she earned an "Acting Shakespeare Certificate" at London's Royal Academy of Dramatic Art.
Goodwin first had roles in the popular NBC television programs Law & Order and Ed before appearing in the Comedy Central television movie Porn 'n Chicken. She later had substantial roles in the films Mona Lisa Smile, Win a Date with Tad Hamilton!, Walk the Line — in which she portrayed Vivian Liberto, Johnny Cash's first wife — and Birds of America. She also played Dori Dumchovic in the dark comedy Love Comes to the Executioner. Goodwin played a leading role as Margene Heffman, the third wife in a polygamous family, on the HBO original series Big Love, which concluded on March 20, 2011. Goodwin has recurring voice roles in the Cartoon Network show Robot Chicken, the animation of which her younger sister Melissa Goodwin is involved.
In 2008, Max Mara honored Goodwin with a "Face of the Future" award, an award recognizing up and coming women in film. Goodwin starred as Gigi in He's Just Not That into You, which was released in February 2009. For this role, she received a nomination for the People's Choice Award for Breakout Movie Actress. In April 2009 she began filming Ramona and Beezus (playing "Aunt Bea").
Since 2011, Goodwin has played a leading role in the ABC fantasy drama series Once Upon a Time. She plays both the fairy tale heroine Snow White and her real world counterpart, schoolteacher Mary Margaret Blanchard. Goodwin voiced Judy Hopps, the rabbit police officer and main protagonist, in Walt Disney Animation Studios' 2016 comedy film Zootopia.
Goodwin dated actor Chris Klein for two years before breaking up in 2008. She later started dating actor Joey Kern and they became engaged in December 2010. They ended the engagement in May 2011. Goodwin subsequently began dating her Once Upon a Time co-star Josh Dallas in fall 2011. Goodwin and Dallas became engaged in October 2013, and married on April 12, 2014 in California. Together, Goodwin and her husband have two sons, one born in 2014 the other born in 2016.
In 2013, Goodwin stated that after leaving Memphis, she "...up and left Judaism for a very long time," and that, "For 10 years, there was nothing. No ritual. No tradition. No community." She later reconnected with her faith, and has said, "I was a Jew by birth, and now I'm a Jew by choice."
In May 2017, it was announced that Goodwin, along with Dallas, would not be returning as series regulars for the seventh season of Once Upon a Time. However, Goodwin revealed that both she and Dallas would return in whatever capacity they could as recurring guest stars.
Gallery of behind the scene stills released to promote the actor.