Bennett, who declined to give her age, has worked as a voice-over actor since the 1970s and said she had no idea Apple would use her voice for Siri when she first laid down the audio tracks in 2005.
The first iPhone hadn't even been released at that time and when she recorded the audio, it was for software company ScanSoft, CNN reported Friday.
"A colleague emailed me [about Siri] and said, 'Hey, we've been playing around with this new Apple phone. Isn't this you?'" she said.
"Oh, I knew," she added. "It's obviously me. It's my voice."
Apple won't confirm Bennett is the voice behind Siri, but professionals who have worked with her voice said they're sure it's her. An audio-forensics expert with 30 years experience in the industry said after studying both voices, he's 100 percent sure it's Bennett.