However, the 22-year-old had no idea about her new title until she was asked by Access All Areas during an interview in Sydney yesterday how she felt about knocking Angelina Jolie off the top of Forbes' list.
"Oh wow," a clearly embarrassed Stewart said, just hours after the news hit the internet. "What are you talking about? I didn't know that."
While her bank balance proves otherwise, sitting alongside SWATH director Rupert Sanders at Sydney's exclusive Park Hyatt hotel yesterday afternoon, Stewart looked like any other 20-something girl, dressed casually in worn-out leggings and a grey flannel shirt.
Even at the Australian premiere of SWATH on Tuesday night, she ditched her Christian Louboutin heels for a pair of comfy Converse sneakers.
"I just don't like teetering over all those young girls," she said. "I want to be able to run around and talk to them. I acknowledge the heels do look better, but that's OK."
So is she uncomfortable with her new title?
"No, I think pressure is kind of a big part of the job and I really appreciate pressure, but it's not really from stuff like that" she said. "Any pressure I feel is self-inflicted."
Stewart was last in Australia to promote the massively successful Twilight. However, she said the reception she received at the SWATH premiere on Tuesday in Bondi, which saw some fans camp out for 48 hours to get a glimpse of the star, was just as emphatic.
"I got really emotional when I got there," she said. "We've got lucky enough to share that energy and that feeling with so many people with Twilight but when I got there for Snow White and saw the same thing it was baffling. It was really cool."
Cameron Diaz, who brought in $US34 million in the past 12 months with films like What to Expect When You're Expecting and Bad Teacher, was second on Forbes' list. Oscar winner Sandra Bullock was third with $US25 million in earnings between May 2011 and May 2012 while Jolie was fourth with $US20 million.
'I just don't like teetering over all those young girls (on high heels) … I want to be able to run around and talk to them. I acknowledge the heels do look better, but that's OK.' KRISTEN STEWART