The legislative branch of the U.S. federal government is mainly Congress , which is made up of two parts: the House of Representatives and the Senate.

Quick Scoop: Who makes it up?

  • Congress : The central body of the legislative branch, created by Article I of the Constitution.
  • House of Representatives :
    • 435 voting members, elected from districts based on state population.
* Plus 6 non‑voting members representing Washington, D.C., Puerto Rico, and four U.S. territories.
  • Senate :
    • 100 Senators, 2 from each state, regardless of population.

These elected officials (Representatives and Senators) are the people who actually sit in Congress and write, debate, and vote on laws.

Supporting pieces inside the branch

In addition to the House and Senate, several agencies are considered part of, or closely tied to, the legislative branch because they support Congress’s work.

  • Library of Congress – provides research and information to lawmakers.
  • Government Publishing Office (GPO) – publishes official government documents, including laws and congressional reports.

These bodies don’t vote on laws but help Congress do its job effectively.

In one line

So, when someone asks “who makes up the legislative branch,” they’re talking about the U.S. Congress — the House of Representatives and the Senate — plus a set of support agencies that help them carry out lawmaking.

TL;DR: The legislative branch is made up of Congress (House of Representatives and Senate) and supporting legislative agencies like the Library of Congress and Government Publishing Office.

Information gathered from public forums or data available on the internet and portrayed here.