Johnny, 51, and Amber, 28, met on the set of 2011 film The Rum Diary. They went public as a couple in 2012 after Johnny split from his longterm partner, Vanessa Paradis, with whom he has two children, Lily-Rose, 15, and Jack, 12.
According to PageSix, the ceremony in the Bahamas will still be a relatively small affair, with around 50 people, including Johnny's children, attending.
It is thought many of the guests will stay on Depp's 156ft yacht, called Vajoliroja.
A source told the site that the couple picked this weekend as it fitted in with their work schedules, saying, "She's filming a movie in London, and he's getting ready to film the next Pirates of the Caribbean in Australia. So this is the only time that everyone could get together."
Reports suggest Amber will wear a gown by British designer Stella McCartney for the ceremony.
This will be the second marriage for Johnny, who wed makeup artist Lori Anne Allison in 1983. He dated Vanessa Paradis for 14 years, but the couple never married. Johnny has also been engaged to Winona Ryder, Jennifer Grey and Sherilyn Fenn.
According to the Daily Mail, the Mortdecai star is very excited about making Amber his wife and celebrating in the Bahamas, with a source saying: "He's completely in love and can't wait!"
Congrats to the happy couple.
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