He may go by "The Prince of Wales," but what's his technical surname? It's rarely ever used, and it's definitely not known by most fans or the common public, but William does have a last name. And, click below to find out what it is....
Prince William's official last name is: Mountbatten-Windsor.
That is quite a mouthful. The name comes from the merging of names of the Queen and Prince Phillip in 1960. Her last name was Windsor, and his was Mountbatten.
And, unless The Prince of Wales (Prince William) chooses to alter the present decisions when he becomes king, he will continue to be of the House of Windsor and Kate and his grandchildren will use the surname Mountbatten-Windsor! [Royal.gov.uk]
Internet searches for "What is Prince William's last name" are up 1199 percent this week. [Today]