For nearly 120 years after the founding of Congress in 1789, most U.S. Representatives conducted all of their business from their individual desks on the House Floor. That changed in 1908, when the House of Representatives opened the first House Office Building (the present-day Cannon building) and Representatives were assigned offices to support them in their work. The advent of designated office space had profound repercussions on some of the institution’s basic functions.

Over time, the growth of congressional offices and staff s necessitated the construction of additional House office buildings: the “New House Office Building” (now the Longworth building) in 1933 and the Rayburn House Office Building in 1965. As new buildings opened, offices were expanded from single rooms to multi-room suites. Today, there are 440 Member offices spread across the three buildings. At the end of each Congress, as Members retire, vacant offices are reassigned to Members according to seniority.

Some of America’s most notable politicians have used these rooms. The table below provides a guide to Cannon offices used by Members who served as Speakers of the House. It is also available on the Clerk of the House’s Web site, clerk.house.gov.

Room histories and office assignments for other notable Members of the House of Representatives are available from the Office of the Clerk. For more information, please contact the Clerk’s Office of History and Preservation at info@clerkweb.house.gov, or (202) 226-1300.