As soon as Hansard's apprenticeship expired, he started for London with only a guinea in his pocket, and became a compositor in the office of John Hughs (1703–1771), printer to the British House of Commons.
Among those whose friendship Hansard won in the exercise of his profession were Edmund Burke, Samuel Johnson and Robert Orme, while Richard Porson praised him as the most accurate printer of Greek.
The promptitude and accuracy with which he printed parliamentary papers were often of the greatest service to government—on one occasion the proof-sheets of the report of the Secret Committee on the French Revolution were submitted to Prime Minister William Pitt the Younger 24 hours after the draft had left Pitt's hands.
He devised numerous expedients for reducing the expense of publishing the reports; and in 1805, when his workmen went on strike at a time of great pressure, he and his sons themselves set to work as compositors.
From 1809 this company printed the official reports of debates and proceedings in the Parliament of the United Kingdom, and owned the publication from 1812.