Prince William turned 29 on Tuesday, June 21, but does not appear to have any plans for a big party.
The prince, the son of Prince Charles and the late Princess Diana, is second in line to the British throne and serves as a helicopter search and rescue pilot in the Royal Air Force.
Palace officials told ABC News, that William planned to mark his birthday at work at a UK military base near Wales and may even pull a 24-hour shift.
People magazine said William would spend the day in his new home of Anglesey, North Wales and added that the prince will be on duty and have a "normal working week." (Check out which other celebrities celebrate birthdays in June.)
"William's birthdays were very normal, with friends," Dickie Arbiter, the Queen's press secretary during William's childhood, told ABC program "Good Morning America." "I remember him running around the palace in his Army fatigues."
William is meanwhile preparing for a trip to the United States and Canada in July with his new wife Kate Middleton, now known as Catherine, Duchess of Cambridge.
This marks their first North American trip as a royal couple. The two plan to tour Canada from June 30 to July 8, with stops in Ottawa, Ontario, Montreal, Quebec City and Calgary, Alberta. On July 8, William and Kate will fly to Los Angeles and are expected to depart on July 10.
The two married in London on April 29 in a ceremony watched by millions of people around the world, including more than 22 million viewers in the United States. Last month, the two honeymooned in Seychelles, an archipelago on the Indian Ocean.
William's brother, Prince Harry, also celebrated his birthday in September 2010 by continuing his military training to become an Apache attack helicopter pilot. It was reported earlier this month that the 26-year-old prince, who has since completed the course, may return to Afghanistan, where he served with the British military for several weeks, starting in 2007.