But it's still less than what The Philosopher's Stone (called The Sorcerer's Stone in the States) took on its first night. That took a whopping £20.4 million.
Potter was at its peak
"We're a little but under that, but we're still going to be in the stratosphere," said a Warner Bros spokesman. "We're on our way to a fantastic weekend."
But the Chamber of Secrets is still going to have its place in cinema history. It's thought it'll be number three in the biggest-ever film charts for making the most money in one weekend.
But it'll be behind Spider-Man and The Philosopher's Stone.
And it'll boot Star Wars: Episode II - Attack of the Clones out of the top three.
Warner Bros says it's not surprised COS isn't doing quite as well as the first film, because people were so desperate to see Harry Potter on the big screen for the first time, that they can never recapture that again.
"The first movie was really part of a cultural event," the spokesman said. "I think 'Potter' at that moment was truly at its peak. The anticipation of that film went way beyond what you'd see for a normal movie."
Hear Story
Daniel Radcliffe COS: full interview
Vote for the cutest Potter boy
