William Nicholson, English-Australian politician, 3rd Premier of Victoria (died 1865)

William Nicholson was an Australian colonial politician who became the third Premier of Victoria. He is remembered for having been called the "father of the ballot" due to his responsibility in introducing the secret ballot in Victoria. Due to this significant legacy, Nicholson Street, a major north–south traffic artery in modern Melbourne, is named after him.

The premier of Victoria is the head of government of the state of Victoria in Australia. The premier leads the Cabinet of Victoria and selects its ministers. The premier is appointed by the governor of Victoria, must be a member of the Victorian Legislative Assembly, and command confidence in the lower house of the Parliament of Victoria. The premier is usually the leader of the political party that holds a majority of lower house members.