Prince William and his wife Catherine will visit the Pacific islands of Solomon and Tuvalu in September as part of the Queen's Diamond Jubilee celebrations.
St James's Palace has confirmed the dates for the visit, which will also include Singapore and Malaysia.
The Duke and Duchess of Cambridge, however, will not be visiting Australia or New Zealand.
Instead, William's father and heir to the throne, Prince Charles, will visit the two countries later this year, most likely in November. His wife Camilla will accompany him.
Other senior members of the royal family are visiting Commonwealth countries this year, while the Queen and Prince Philip are making special visits throughout the United Kingdom.