The detailed plan said only the couple's closest family members and friends would be able to witness the wedding close up, while more than 1,000 other guests would see the ceremony on video screens from behind a partition blocking the altar from view, The Daily Telegraph reported Saturday.
The couple have strayed from orthodoxy and won't have a bride's side and a groom's side. Members of the Spencer family, relatives of Prince William's late mother, Princess Diana, will sit next to the Middletons.
The queen and members of the royal family will sit across the aisle from the Middleton family. They will be closest to the sanctuary, where the bride and groom will stand.
British Prime Minister David Cameron is among the guests. He will sit on the south side of the Abbey along with members of his Cabinet and members of Parliament.