The bride is expected to wear an "elegant" Marchesa gown, a source told E! News, a dress she chose over a vintage Chanel gown, which was also an option.
"It's custom-made, white, and cost her ,000," the source told the website of Nicole's wedding day pick.
Additionally, E! News reported that the beautiful bride will have Byron of Byron+Tracy do her hair.
Expected to be held at her dad, Lionel Richie's Beverly Hills compound, E! News reported that Samantha Ronson will be a bridesmaid at the wedding, while Joel and Nicole's adorable 2-year-old daughter, Harlow, will be the flower girl.
Ashlee Simpson-Wentz is expected among the guests at the intimate nuptials.
As previously reported on AccessHollywood.com, delivery trucks were seen arriving at Lionel's Beverly Hills home just last week.
Nicole and Joel have been together since 2006 and have two children together — son Sparrow James Midnight, 1; and Harlow, who will turn 3 in January.
Nicole announced her engagement to the Good Charlotte frontman during a trip to "The Late Show with David Letterman" in February.
It is the first marriage for both.
Nicole was previously engaged to the late Adam Goldstein – aka DJ AM. However, the couple split in 2005 after a nine-month engagement.
Nicole's rep had no comment when contacted by Access Hollywood.
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