The office of William and his father Prince Charles,Clarence House,refused to give any details of how Middleton would mark her big day, saying only that she was spending it "privately."
British media said that Kate who is five months older than her royal fiance was expected to enjoy low-key festivities with her family and friends as she prepares for her April 29 nuptials.
Ingrid Seward, editor of Majesty magazine, a publication focusing on the royal family said"She will probably want to keep a low profile because the rest of her life will be high profile,"
"There are a lot of parties coming up so she might just want some really, really close friends and family with her or it could be just her and William."
Prince William is serving as a Royal Air Force search and rescue helicopter pilot in Anglesey, Wales.
The couple were seen in public on Saturday at the wedding of one of William's friends, with Kate sporting a tailored black velvet coat, a black dress with a plunging sheer neckline and a jaunty black beret.
William was an usher for the wedding in the northern village of Boroughbridge of Harry Aubrey-Fletcher, a schoolmate from the prince's time at the elite Eton College, and Louise Stourton.
The News of the World tabloid, Britain's biggest selling newspaper, focused instead on whether or not the country's future queen was wearing a bra.
William and Kate earlier this week released new details of the plans for their wedding at London's Westminster Abbey, including that they would be married by the Archbishop of Canterbury, Rowan Williams.
They will also make a procession in a horse-drawn carriage through some of the capital's most historic sites after they have tied the knot.
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