"An insider" was the only source named by the celebrity news magazine, and no clear confirmation - or denial - had been issued as of this morning by the couple's publicists, other news outlets said.
When gossip site TMZ contacted Jada's rep, Karynne Tencer, she said, "What? In Touch said that? I know nothing about this ... Lord. I'm going back to bed."
The show-biz couple got married in 1997, and had two children together, Willow, who had a hit song with "Whip My Hair," and Jaden, who costarred with his father in Pursuit of Happyness, and starred in a remake of The Karate Kid.
Trey is Smith's son from an earlier marriage.
Whether the Smiths have had an open marriage, accepting of occasional flings, has been widely discussed - and distorted. He explained a couple of years ago that they openly admit being attracted to other people, and would ask permission of the other first before having sex with someone else.
But apparently neither has publicly admitted to having any affairs.
Most recently, Will Smith made news in Philadelphia, with a meetup with director M. Night Shyamalan and couple of on-stage appearances, including one Sunday for friend and hip-hop pioneer Lady B.
The Smith family was recently featured on the cover of Architectural Digest, showing off their Calabasas, Calif., mansion, and talking about all the love that went into its handcrafted furnishings.
"For Will and me this home was always a spiritual endeavor," Jada said.
The Smiths were also among the celebrity guests on the May finale of The Oprah Winfrey Show.
Another endeavor together was New Village Leadership Academy, a Calabasas private school they funded. After rumors of involvement with Scientology, the couple denied any affiliation between the school or themselves to the psychology-based religion.
Will Smith also made headlines during the filming of Men in Black III by parking his oversize trailer on a Manhattan Street. At the mayor's request, he moved it and a separate trailer for his gym to a paid parking lot.
Smith turned a starring role on TV's Fresh Prince of Bel-Air into a film career, including such hits as Bad Boys, Independence Day, I Robot, Ali, Enemy of the State, and Hancock.
Contact staff writer Peter Mucha at 215-854-4342 or firstname.lastname@example.org.