William Thomas Stead (5 July 1849 – 15 April 1912) was an English newspaper editor who, as a pioneer of investigative journalism, became a controversial figure of the Victorian era. Stead published a series of hugely influential campaigns whilst editor of The Pall Mall Gazette, including his 1885 series of articles, The Maiden Tribute of Modern Babylon. These were written in support of a bill, later dubbed the "Stead Act", that raised the age of consent from 13 to 16.

Stead's "new journalism" paved the way for the modern tabloid in Great Britain. He has been described as "the most famous journalist in the British Empire". He is considered to have influenced how the press could be used to influence public opinion and government policy, and advocated "Government by Journalism". He was known for his reportage on child welfare, social legislation and reformation of England's criminal codes.

Stead died in the sinking of the RMS Titanic.

William Thomas Stead was born on 5 July 1849 in Embleton, Northumberland, the son of the Reverend William Stead, a poor and respected Congregational minister, and Isabella (née Jobson), a cultivated daughter of a Northumberland farmer, John Jobson of Warkworth. A year later the family moved to Howdon on the River Tyne, where his younger brother, Francis Herbert Stead, was born. Stead was largely educated at home by his father, and by the age of five he was already well-versed in the Holy Scriptures and is said to have been able to read Latin almost as well as he could read English. It was Stead's mother who perhaps had the most lasting influence on her son's career. One of Stead's favourite childhood memories was of his mother leading a local campaign against the government's controversial Contagious Diseases Acts – which required prostitutes living in garrison towns to undergo medical examination.

From 1862 to 1864, he attended Silcoates School in Wakefield until he was apprenticed to a merchant's office on the Quayside in Newcastle upon Tyne, where he became a clerk.

Stead contributed articles to the fledgling liberal Darlington newspaper The Northern Echo from 1870 and despite his inexperience was appointed editor of the newspaper in 1871. Aged just 22 Stead was the youngest newspaper editor in the country. Stead used Darlington's excellent railway connections to his advantage, increasing the newspaper's distribution to national levels. Stead was always guided by a moral mission, influenced by his faith, and wrote to a friend that the position would be "a glorious opportunity of attacking the devil".

In 1873 he married his childhood sweetheart, Emma Lucy Wilson, the daughter of a local merchant and shipowner; they would eventually have six children. In 1876 Stead joined a campaign to repeal the Contagious Diseases Act, befriending the feminist Josephine Butler. The law was repealed in 1886.

He gained notoriety in 1876 for his coverage of the Bulgarian atrocities agitation. He is also credited as "a major factor" in helping William Ewart Gladstone win an overwhelming majority in the 1880 general election.