A bill becomes a law in Congress by moving through a fixed sequence: a member of the House or Senate introduces it, a committee reviews and reports it, the full chamber debates and passes it, the other chamber does the same with identical text, and the President signs it. If the President vetoes the bill, Congress can still enact it with a two-thirds vote in both chambers. Most bills never finish the trip.
Step 1: A Member Introduces the Bill
Every bill starts with a sponsor, a senator or representative who formally introduces it in their chamber. House bills carry an “H.R.” prefix, Senate bills carry “S.,” and each is numbered in the order it is introduced.1U.S. Senate. Types of Legislation Any member can sponsor a bill, and there is no cap on how many a single legislator can file.
One constitutional rule affects where a bill can start. The Origination Clause requires all revenue-raising bills to begin in the House, though the Senate can then amend them like any other legislation.2Congress.gov. Constitution Annotated – Article I Section 7 Congress also uses joint resolutions, which follow the same process and carry the same legal force as bills. A joint resolution proposing a constitutional amendment is the one exception: it needs a two-thirds vote in both chambers and then goes to the states, not the President.3House.gov. Bills and Resolutions
Step 2: Committee Review
Once introduced, the bill is referred to the standing committee with jurisdiction over its subject. This is where most bills quietly die. The committee chair controls the agenda and decides which bills get hearings, making this the single most powerful filter in the process. If the chair does not want a bill to move, it usually will not.
Bills that get attention go through hearings, where the committee takes testimony from experts, officials, and the public. Next comes a markup session, where members debate the actual text and offer amendments. The committee then votes on whether to “report” the bill to the full chamber, usually accompanied by a written report explaining what the bill does and why.
The House has one escape hatch when a committee refuses to act. If 218 members sign a discharge petition, the bill can be pulled out of committee and sent to the floor. Discharge petitions rarely succeed, but they occasionally break a bill loose when it has broad support the chair opposes.
Step 3: Floor Debate and Vote in the First Chamber
In the House
Once reported, a House bill waits its turn on the calendar. For significant legislation, the Rules Committee writes a “special rule” that sets the terms of debate: how much time is allotted and which amendments, if any, can be offered. Most bills brought up under a special rule get one hour of general debate, split evenly between supporters and opponents.4Congressional Research Service. Special Rules in the House of Representatives A closed rule blocks amendments entirely; an open rule permits any germane one.
After general debate, the House often resolves into the Committee of the Whole, a procedural setup that moves amendments faster. Under the five-minute rule, the amendment’s sponsor and one opponent each get five minutes.5Congressional Research Service. The Committee of the Whole Once amendments are finished, the Committee of the Whole reports back and the full House votes on final passage. A simple majority of members present and voting passes the bill, provided a quorum of 218 is present.6Congress.gov. Constitution Annotated – Article I Section 5
In the Senate
The Senate runs on a different premise: debate is nearly unlimited. Any senator can hold the floor until the chamber collectively agrees to stop, which is what makes the filibuster possible. To force debate to end, the Senate must invoke cloture, and cloture takes three-fifths of the full Senate, typically 60 votes. Once cloture passes, debate is capped at 30 more hours before the final vote.7U.S. Government Publishing Office. United States Senate Manual – Rule XXII
On routine matters, senators avoid formal filibusters through unanimous consent agreements, negotiated deals that set time limits, list allowed amendments, and schedule votes. Once adopted, a unanimous consent agreement is binding and can only be changed by another one.8United States Senate. The First Unanimous Consent Agreement In recent years these agreements have sometimes built in a 60-vote passage threshold, replacing formal cloture with a streamlined equivalent.9Congressional Research Service. Unanimous Consent Agreements in the Senate
Final passage in the Senate takes a simple majority of those present and voting, the same as the House. But because of the filibuster, most contested legislation effectively needs 60 votes just to reach that final vote. That distinction catches many people off guard.
Step 4: The Second Chamber Acts
A bill that passes one chamber goes to the other, and the entire sequence repeats: referral, committee, floor debate, final vote. The Constitution requires both chambers to approve identical text before anything can go to the President.2Congress.gov. Constitution Annotated – Article I Section 7 Passage without changes is uncommon.
Step 5: The Two Chambers Reconcile Their Versions
When the House and Senate pass different versions of a bill, they have to produce one common text. Congress historically used conference committees, temporary panels of members from both chambers who negotiate a compromise version and send back a conference report for an up-or-down vote in each chamber. Conference committees have grown less common. Party leaders now often negotiate informally, or the chambers trade amendments back and forth, a practice sometimes called ping-ponging, until both sides land on the same language.
The method does not matter; the result does. Both chambers must pass word-for-word identical text. If they cannot agree, the bill dies and would have to start over in a future session.
The Reconciliation Exception for Fiscal Bills
One important shortcut sits outside the standard Senate process. Budget reconciliation lets certain tax and spending measures pass with 51 votes instead of 60, and debate is capped at 20 hours, which blocks a filibuster.10Congressional Research Service. The Budget Reconciliation Process The tradeoff is strict limits on what can ride along. Under the Byrd Rule, every provision must directly affect federal revenue or spending, and any senator can object to strip out an “extraneous” one. A reconciliation bill also cannot increase the federal deficit beyond the period set by the underlying budget resolution.11Congressional Research Service. The Byrd Rule in the Senate Congress can only use reconciliation after adopting a budget resolution with specific instructions to committees, so it is not available on demand for any bill a majority happens to like.
Step 6: The Bill Goes to the President
Once both chambers approve identical text, the bill is enrolled, printed on parchment, signed by the Speaker of the House and then by the presiding officer of the Senate, and sent to the President.12Congressional Research Service. Enrollment of Legislation The Constitution gives the President four choices:2Congress.gov. Constitution Annotated – Article I Section 7
- Sign the bill, and it becomes law immediately.
- Veto the bill, returning it to the chamber of origin with written objections. Congress can override only with a two-thirds vote in both the House and the Senate, which rarely happens.13National Archives and Records Administration. The Presidential Veto and Congressional Veto Override Process
- Do nothing while Congress is in session. After ten days (Sundays excluded), the bill becomes law without a signature.14Library of Congress. Constitution Annotated – Article I Section 7 Clause 2
- Do nothing after Congress adjourns within that ten-day window. The bill dies. This is a pocket veto, and Congress cannot override it; the bill must be reintroduced fresh.14Library of Congress. Constitution Annotated – Article I Section 7 Clause 2
The President has to accept or reject the whole bill. There is no line-item veto. The Supreme Court struck down a short-lived line-item veto statute in 1998, holding that the Constitution requires each bill to be presented for approval or rejection as a whole.
What Happens After the President Signs
A signed bill does not simply appear in the law books. The Office of the Federal Register assigns it a public law number in the format “Public Law [Congress number]-[sequence number]” and prepares it for publication. Each new law is first printed as a slip law, an individual pamphlet, and later compiled into the United States Statutes at Large, the permanent bound record of every law Congress enacts in a session.15National Archives. Federal Register Publications System – Public Laws If the new law changes existing federal law, those changes are folded into the United States Code, which organizes permanent federal statutes by subject across 54 titles. That codification is what lets courts, agencies, and the public look up the current state of federal law without wading through every bill Congress has ever passed.