What is a bill?

A bill is a legislative proposal brought before Congress in either the House or the Senate. Bills introduced in the House are assigned sequential numbers in the order in which they are introduced and are preceded by "H.R.". Bills introduced in the Senate are assigned sequential numbers preceded by "S.".

• The House adopted a sequential numbering system in which bills were numbered consecutively for an entire Congress in the 15th Congress (1817), and the Senate began using the same numbering system in the 30th Congress (1847). Prior to that time, the Senate numbering system provided that sequential numbering started anew at the beginning of each congressional session.
• Bills within a single numbering sequence may be either public or private. Public bills pertain to matters that affect the general public or classes of citizens and become public laws if enacted. Private bills are concerned with relief or related actions with limited applicability and, if enacted, become private laws. The distinction between public and private bills has not always been clear, especially in bills from the earlier Congresses.