How a Bill Becomes a Law in the United States

From a lawmaker's idea to the President's signature, here is every step a bill takes through Congress — and where most bills stall.

Every federal law in the United States starts the same way: as a bill. Thousands are introduced in each two-year session of Congress, yet only a small share ever become law. Understanding the path a bill takes makes it much easier to follow news stories about votes, filibusters and vetoes.

1. A bill is introduced

Only a member of Congress can formally introduce a bill. In the House of Representatives, a member drops it into a box called the "hopper." In the Senate, a senator introduces it from the floor or files it with the clerk. Ideas for bills can come from anywhere — constituents, interest groups, the White House or lawmakers themselves — but a member must sponsor it.

The Constitution sets one important rule here: bills for raising revenue, such as tax bills, must start in the House (Article I, Section 7). Most other bills can begin in either chamber.

2. Committee review

After introduction, the bill is referred to the committee that handles its subject — agriculture, armed services, judiciary and so on. This is where most of the real work, and most of the stalling, happens. A committee or one of its subcommittees may hold hearings, invite expert testimony and then "mark up" the bill by debating and amending it line by line.

If the committee votes to approve it, the bill is "reported" to the full chamber. If the committee never acts, the bill simply dies when the session ends. This quiet death is the fate of most bills.

3. Floor debate and vote

In the House, the Rules Committee usually decides how long a bill will be debated and whether amendments are allowed. Then the full House debates and votes. A simple majority of members voting is needed to pass it.

The Senate works differently. Senators traditionally have the right to extended debate, which allows a filibuster — keeping debate going to block a vote. Ending debate requires "cloture," which for most legislation takes 60 votes. That is why news coverage often says a bill "needs 60 votes in the Senate" even though final passage requires only a simple majority. Some budget-related bills can move through a special process called reconciliation that is not subject to the filibuster.

4. The other chamber

A bill passed by one chamber goes to the other, where it repeats the committee and floor process. Both chambers must pass the exact same text. If their versions differ, they resolve the differences either by sending amended versions back and forth or by forming a conference committee of members from both chambers to write a compromise. The compromise then needs a new vote in both the House and Senate.

5. The President acts

Once both chambers agree, the final "enrolled" bill goes to the President, who has 10 days (Sundays excepted) to act:

• Sign it — the bill becomes law.
• Veto it — the bill is returned to Congress with the President's objections.
• Do nothing — if Congress is in session, the bill becomes law without a signature after 10 days. If Congress has adjourned and the President does not sign, the bill does not become law. This is called a pocket veto.

6. Overriding a veto

Congress can override a veto with a two-thirds vote in both the House and the Senate. That is a high bar, so overrides are rare. When they succeed, the bill becomes law without the President's approval.

How to follow a bill yourself

Every bill gets a number, such as H.R. 1234 for House bills or S. 567 for Senate bills. You can search that number on Congress.gov to see its full text, sponsors, committee actions and votes. Tracking the official record is the best way to cut through confusing headlines about what a bill does and where it stands.