The 37-year-old socialite said Wednesday on Radio Andy that Lohan had chased her down and "squeezed in the car" in the iconic November 2006 photo featuring Hilton, Lohan and Spears.
"She totally party crashed," Hilton told host Andy Cohen. "We were all at the Beverly Hills Hotel ... Me and Britney wanted to leave to go home. [Lindsay] started, like, chasing us and then squeezed in the car."
"It was literally, like, a two-seater," she said of her vehicle. "She just, like, squeezed in. I didn't want to humiliate her in front of all the paparazzi and be like, 'Get out of my car.' So I was like, whatever."
Hilton returned home with Lohan and Spears, where she and Spears went to sleep. She said Lohan was gone by the time they woke up.
"There was no Uber back then, so she just probably called a cab. I have no idea," the star said.
Hilton paid tribute to her famous outing with Lohan and Spears in November 2017, sharing photos from the night on Twitter.
"11 years anniversary today since the first coming of The Holy Trinity!" she captioned the post.
Hilton and Lohan had a highly publicized falling out in the 2000s. Hilton called the actress a "pathological liar" in an Instagram comment in July and stood by her remark in an interview with E! News later in the month.
"Just saying a fact. Fact of life," the star said.
Hilton said she wishes Lohan well with her new MTV series, Lindsay's Beach Club.
"Good luck to her. I wish her the best," she said.