How does a bill become a law? The US process, step by step

A bill becomes a law in the United States when both chambers of Congress, the House of Representatives and the Senate, pass exactly the same text and the president signs it. If the president vetoes it, it can still become law if two-thirds of each chamber vote to override. Between introduction and signature come committees, floor votes and negotiations, and most bills never get far: the committee that does the first review lets the great majority die.

In short

• Any member of Congress can introduce a bill, but a committee decides whether it goes anywhere, and most die there.
• Both chambers must pass identical words. Differences are settled by a conference committee or by sending amendments back and forth.
• The president signs, vetoes, or waits: ten days without a signature makes it law, unless Congress has adjourned, which kills it with a pocket veto.

Who can introduce a bill?

Only a member of Congress can formally introduce a bill, though ideas come from everywhere: the president, federal agencies, interest groups, states and voters. In the House, a member drops the bill into a wooden box called the hopper. In the Senate, a senator hands it to a clerk or introduces it from the floor. The bill gets a number, such as H.R. 7152 for a House bill or S. 1 for a Senate one, which it keeps until the Congress ends. The Constitution requires one kind of bill to start in the House: bills for raising revenue.

What happens in committee?

The bill is referred to the committee, or committees, that cover its subject. This is where most of the work happens and where most bills end. A committee or one of its subcommittees can hold hearings, rewrite the bill line by line in a session called a markup, and vote to report it to the full chamber. Or it can do nothing, which is the most common outcome. A bill no committee acts on simply expires when the two-year Congress ends.

The numbers show how steep the path is. Bills are numbered in the order they are introduced, and in the 118th Congress, which sat from 2023 to 2025, House bills ran past H.R. 10500 and Senate bills past S. 5300, so members introduced more than 15,000 bills. Only 274 measures became law, by the Pew Research Center's count. Fewer than 2 bills in 100 were enacted. Many bills are introduced to make a point, signal a position or start a conversation, with little expectation of passing.

How does a bill pass the House and the Senate?

The two chambers run their floors very differently.

In the House, the majority controls the schedule. Major bills go first to the Rules Committee, which writes a "rule" for each one: how long the debate lasts and which amendments, if any, may be offered. A simple majority of those voting passes the bill, which is 218 when all 435 seats are filled and everyone votes. Many less contested bills skip that route and pass "under suspension of the rules", with 40 minutes of debate, no amendments and a two-thirds vote. If leaders won't bring up a bill, 218 members can sign a discharge petition to force it out of committee.

The Senate has no equivalent of the Rules Committee and almost no limits on debate. Much of its business moves by unanimous consent, so a single senator can slow things down by objecting. A bill that a determined minority opposes needs 60 votes to end debate, which is the filibuster. Only then does the final vote, by simple majority, take place.

What happens when the House and Senate pass different versions?

The president can sign only one text, so the chambers must agree word for word. There are three ways to get there. One chamber can simply accept the other's version. The chambers can trade amendments back and forth, sometimes called ping-pong, until one side agrees. Or they can appoint a conference committee of members from both, which writes a compromise that each chamber must then pass without changes. Conference committees were once the standard route for major bills and are used much less often now.

What can the president do with it?

Once both chambers pass the same text, it is printed as an enrolled bill and sent to the president. Under Article I, Section 7 of the Constitution, the president then has ten days, not counting Sundays, and four choices.

Choice	What happens
Sign it	It becomes law
Veto it	It returns to Congress with the president's objections, and dies unless two-thirds of both chambers vote to override
Do nothing while Congress is in session	After ten days, Sundays excepted, it becomes law without a signature
Do nothing after Congress adjourns	It dies, a pocket veto, and cannot be overridden

Vetoes are rarely overridden. By the Congressional Research Service's 2016 count, presidents had vetoed 2,572 bills since 1789 and Congress had overridden 110 of them, about 4%. Usually the threat of a veto is enough to reshape a bill before it arrives. The president's powers over legislation are mostly this one: the power to say no.

A new law goes to the National Archives' Office of the Federal Register, which gives it a public law number, such as Pub.L. 88-352, and publishes it in the Statutes at Large. Its story may not end there: the courts can later be asked whether it fits the Constitution.

One bill, every stage: the Civil Rights Act of 1964

The Civil Rights Act shows each step, including the obstacles. The dates and votes below come from the Senate Historical Office and the National Archives.

1. June 1963. After President John F. Kennedy proposed civil rights legislation, the bill was introduced in the House as H.R. 7152 and referred to the Judiciary Committee.
2. Autumn 1963. The Judiciary Committee reported it, and it reached the Rules Committee, whose chairman, Howard Smith of Virginia, opposed it and held it back.
3. December 1963. Supporters circulated a discharge petition to pry the bill out of the Rules Committee. The committee released it early in 1964.
4. 10 February 1964. The full House passed the bill.
5. 26 February 1964. In the Senate, Majority Leader Mike Mansfield placed it straight on the calendar, skipping the Judiciary Committee, whose chairman was also an opponent.
6. 9 March to 10 June 1964. Southern senators filibustered. On 10 June the Senate voted cloture, 71 to 29, the first time it had ever cut off a filibuster on a civil rights bill.
7. 19 June 1964. The Senate passed an amended version, 73 to 27.
8. 2 July 1964. The House accepted the Senate's version, so no conference was needed, and President Lyndon B. Johnson signed it the same day. It became Public Law 88-352.

That is a year from introduction to signature, with two committees bypassed or forced, a filibuster broken and one chamber giving way to the other.

Why real lawmaking often skips the textbook path

The classic sequence still exists, but many major laws now take shortcuts. Party leaders write bills themselves and send them straight to the floor. Hundreds of pages of spending are bundled into a single omnibus bill passed just before a deadline. Budget reconciliation lets certain tax and spending bills pass the Senate with 51 votes. The political scientist Barbara Sinclair called this pattern "unorthodox lawmaking."

Supporters of the shortcuts say they are the only way to pass anything when the parties are closely divided and the Senate needs 60 votes. Critics say they leave members voting on bills they haven't had time to read and weaken committees, which are where expertise and public hearings happen. Both points describe the same trade between speed and scrutiny. What Congress does covers the other powers of the two chambers, and what democracy is covers the idea of representation that the whole process rests on.

Check yourself

• Without looking back: why do most bills die, and at which stage?
• What are the two ways, other than a conference committee, of settling differences between the House and Senate versions?
• When does a president's silence make a bill law, and when does it kill it?

Sources

• The Legislative Process — U.S. House of Representatives
• Regular Vetoes and Pocket Vetoes: In Brief — Congressional Research Service, 2016
• So far, the 119th Congress is among the least productive of the past 40 years — Pew Research Center, 2026
• List of acts of the 118th United States Congress — Wikipedia
• The Civil Rights Act of 1964 — U.S. Senate Historical Office
• Congress and the Civil Rights Act of 1964 — National Archives, Center for Legislative Archives