Mary Cosby is back for season 7 of The Real Housewives of Salt Lake City, airing now on Bravo, and she remains the cast member around whom the franchise was originally built. Born October 17, 1972, she is 54 years old in 2026, and her story — church, family, and a return to full-time cast status after a break — is unlike any other in the Housewives universe.
Quick Facts
| Full Name | Mary Martha Cosby (née Jefferson, formerly Harris) |
| Age | 54 years old (born October 17, 1972) |
| Birthplace | Salt Lake City, Utah, United States |
| Known For | The Real Housewives of Salt Lake City (2020–present) |
| Occupation | Television personality |
| Role | First Lady of Faith Temple Pentecostal Church |
Who Is Mary Cosby?
Mary Cosby is an American television personality best known as an original cast member of Bravo’s The Real Housewives of Salt Lake City. According to NBCUniversal executive Noah Samton, the show was conceived after producers discovered Cosby, and the rest of the cast was found around her — a rare origin story for a franchise that usually starts with a city, not a person.
On screen, Cosby is famously direct, famously private, and often the cast member least interested in playing the usual Housewives game. That combination has made her both a fan favorite and a lightning rod: viewers tune in for her bluntness, while her castmates frequently find themselves on the other end of it. In 2026, her season 7 return comes after a deeply difficult year, with the death of her son Robert Cosby Jr. in February 2026 at age 23, reported by Variety and Deadline.
Early Life & Background
Cosby was born Mary Martha Jefferson on October 17, 1972, in Salt Lake City, Utah, the youngest of her siblings. Her grandmother, Rosemary “Mama” Cosby, founded Faith Temple Pentecostal Church in 1968, and Cosby grew up inside that church world. Through her marriage, she became First Lady of Faith Temple, a role that has shaped both her public identity and many of the show’s most contested storylines.
She married Dana Harris, divorcing in September 1998, and following her grandmother’s death in January 1997, she married Bishop Robert C. Cosby, her step-grandfather, in September 1998. Cosby has described the marriage as arranged, saying it was “kind of in my grandma’s will for us to marry.” The marriage led to estrangement from her mother, who died in January 2025, and to long-running disputes within the wider family over the church founder’s estate and assets.
Career & Journey
Cosby was announced as a cast member of RHOSLC in September 2020, but her path on the show has been stop-start: after missing the season 2 reunion, she did not return for season 3, came back as a friend of the show in season 4, and was promoted back to a full-time cast member in season 5. That return stuck, and she remains a main cast member in season 7, premiering September 16, 2026.
Off screen, Cosby has defended herself against allegations about Faith Temple, calling claims that it is a cult “false” and “ridiculous,” and the subject was explored in a three-part TLC docuseries, The Cult of the Real Housewife. In September 2024 she sued two executives of United Security Financial, accusing them of embezzlement from church finances. Through all of it, her on-screen role has remained consistent: the original, unfiltered voice at the center of Salt Lake City. For the full season 7 cast, see our Real Housewives of Salt Lake City cast guide.
Facts About Mary Cosby
- She is an original RHOSLC cast member, and the show was conceived after producers discovered her.
- Her grandmother founded Faith Temple Pentecostal Church in 1968.
- She missed the season 2 reunion, sat out season 3, returned as a friend in season 4, and was full-time again from season 5.
- She is the First Lady of Faith Temple Pentecostal Church in Salt Lake City.
- She sued two United Security Financial executives in September 2024 over alleged church-finance embezzlement.
Frequently Asked Questions
How old is Mary Cosby?
Mary Cosby was born October 17, 1972, making her 54 years old in 2026.
What is Mary Cosby known for?
She is best known as an original cast member of The Real Housewives of Salt Lake City and as First Lady of Faith Temple Pentecostal Church.
Is Mary Cosby still on RHOSLC in season 7?
Yes. She is a main cast member in season 7, which premiered September 16, 2026, on Bravo.
Why did Mary Cosby leave RHOSLC?
After missing the season 2 reunion, she did not return for season 3, then came back as a friend in season 4 and full-time in season 5.
Who is Mary Cosby’s grandmother?
Her grandmother was Rosemary “Mama” Cosby, who founded Faith Temple Pentecostal Church in 1968.
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