The former Kate Middleton plans to celebrate her 30th birthday in private after attending a gala film premiere the night before.
Palace officials say the Duchess of Cambridge is planning only low-key celebrations to mark her milestone birthday.
The birthday marks Middleton's first as a member of the royal family.
She dominated Britain's front pages Monday with photographs of her wearing a lacy Alice Temperley gown at the premiere of Steven Spielberg's "War Horse" film.
Middleton has moved into her royal role, specifying a number of charities she will become involved with. She and her husband Prince
William also plan to travel abroad later this year for events related to Queen Elizabeth II's Diamond Jubilee.