Berry started his working life as a journalist and established his own paper, Advertising World, in 1901.

In 1927 they purchased The Daily Telegraph from the 2nd Harry Levy-Lawson, 1st Viscount Burnham, with William Berry becoming its editor-in-chief.

Berry bought out his partners in 1937 and amalgamated The Morning Post with The Daily Telegraph, with himself as chairman and editor-in-chief.

He and ten other wealthy well-wishers each donated £5,000 to the Churchills, allowing them to keep their home, Chartwell, on the condition that it would be presented to the nation upon their deaths.

They had eight children together:[8] Berry died in 1954 and was succeeded in the viscountcy, barony and baronetcy by his eldest son, Seymour.