There are two sessions in each Congress. A session lasts for about one year, or until both houses of Congress decide to adjourn finally for that year. The last 5 sessions of Congress have averaged 296 days in length apiece. Over that 5-year period, the House met for an average of 136 days in each session, and the Senate for an average of 160 days per session. On days when no floor meetings (also called daily sessions) are held, Members may still conduct hearings, may conduct district work periods in their local offices, engage in official travel, or be on holiday.

There have been 106 Congresses completed since the First Congress met in 1789. We are now in the first session of the 107th Congress. The two-year length of a Congress stems from the Constitutional requirement that Members of the House be elected every second year.

Earlier Congresses sometimes divided the two years into as many as 3 sessions. However, since 1933, with adoption of the Twentieth Amendment to the Constitution, Congress has held 2 sessions (with two exceptions during WWII), beginning the annual session on January 3 of each year. It may also choose a day other than January 3 to convene the new session, if provision for an alternate date is made in advance. This has almost always been the case if January 3 happens to fall on a Saturday or Sunday.

All bills and other legislative activity carry over from one session to the next. However, legislation not completed by the end of a Congress dies.

Here is a 30-year look at the days Congress has spent in session:

For a complete list of the beginning and ending date for each Congress, visit the Office of the House Clerk website for U.S. Congress Dates, 1789-Present.