The actress, who turned 46 on Thursday, was spotted running errands in the Hamptons on Friday just hours before her rehearsal dinner. Falchuk, 47, also stepped out (separately) before their big day.
“Gwyneth and Brad both look very happy,” a source tells PEOPLE. “They spent most of the day apart. Gwyneth is very involved in the wedding set up, but at the same time seems very chilled.”
The insider adds, “She also seems very excited!”
The Goop founder opened up to PEOPLE in January about planning her wedding to the American Horror Story producer.
“I’m excited about everything!” the actress told PeopleStyle. “I’ve never had a wedding before. [Paltrow and Martin eloped in 2003.] So even though I’m 45, I sort of feel like a 21-year-old.”
While at the time Paltrow had not begun “any formal plans” for the wedding, the star said she was having fun brainstorming with her best friends.
“It’s kind of fun to talk about with my girlfriends,” she said. “They send me pictures of dresses — they’re as excited about it as I am. It’s pretty cute.”
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The couple announced their engagement on the cover of Paltrow’s Goop Magazine’s Sex & Love issue after dating for over three years.
The Shakespeare in Love actress called their romance her first “adult relationship” despite her previous marriage to Martin.
“For the first time, I feel like I’m in an adult relationship that is sometimes very uncomfortable — because he sort of demands a certain level of intimacy and communication that I haven’t been held to before,” she said in the issue.