Us Weekly reported on its Web site Sunday that the small wedding took place at a resort outside Vancouver, British Columbia. Guests included Scarlett's mother, Melanie Sloan, and her brother, Adrian Johansson, the magazine said.
The couple announced their engagement in May.
"We're just enjoying our time," the actress said last month.
"We're just recently - very recently - engaged. So, you know, we're just taking it easy. And no big plan yet. But it's a good time and we're just ... enjoying our time to be young and engaged.
"I mean, I'm 23. There's no reason to rush into it. Everything feels very natural and relaxed."
Johansson most recently starred in the Woody Allen film "V CB." Reynolds starred on the TV show "Two Guys, a Girl and a Pizza Place" and the romantic comedy "Definitely, Maybe."