Explainers/Congress
How a bill becomes law
The full path a proposal takes from introduction to the president's desk, and the points where most bills die.
5 min read|Updated July 27, 2026
A bill must pass the House and the Senate in identical form before the president can sign it. Most bills never get that far: they are referred to a committee and never scheduled for a vote. Roughly 4 to 6 percent of introduced bills become law in a typical two-year Congress.
- Votes required in the House
- Simple majority, 218 of 435 when all seats are filled
- Votes usually required in the Senate
- 60 to end debate, then 51 to pass
- Votes to override a veto
- Two-thirds of each chamber
- Share of bills that become law
- About 4 to 6 percent
Who can introduce a bill?
Only a member of the House or Senate can formally introduce a bill, though the text is often drafted by the executive branch, an outside group, or nonpartisan legislative counsel. The member who introduces it is the sponsor; others who sign on are cosponsors. Identical bills are frequently introduced in both chambers on the same day as companion bills.
What happens in committee?
The presiding officer refers the bill to the committee with jurisdiction over the subject. The committee may hold hearings, amend the text in a markup session, and vote to report the bill to the full chamber. If the chair never schedules a markup, the bill dies there. This is where the large majority of bills stop.
Why does the Senate usually need 60 votes?
Passing a bill takes a simple majority, but ending debate on it takes 60 votes under the Senate cloture rule. Because any senator can prolong debate, the practical threshold for most legislation is 60. Budget reconciliation bills and most nominations are exceptions and need only a majority.
What if the two chambers pass different versions?
The bill cannot go to the president until both chambers approve identical text. Chambers resolve differences either by one side simply passing the other's version, by amending each other back and forth, or by a conference committee that negotiates a single compromise report each chamber then votes on without amendment.
What are the president's options?
The president can sign the bill, veto it and return it with objections, or take no action. If Congress is in session, a bill left unsigned for ten days excluding Sundays becomes law anyway. If Congress adjourns during that window, the bill dies in a pocket veto. Congress can override a regular veto with two-thirds of each chamber.