Anyone who has followed a Supreme Court confirmation hearing has likely asked: How many justices actually sit on the highest court in the land? The answer—nine—has been fixed for over 150 years, but the reasons behind that number and the political fights to change it tell a fascinating story. This article breaks down the current roster, how we got here, and what the future might hold for the Court’s composition. For another take on institutional structures, see How Many MLB Teams Are There? (2025 Update).

4 related posts

Current number of justices: 9 ·
Chief Justice: John Roberts ·
Longest serving justice: Clarence Thomas (since 1991) ·
Most recent appointment: Ketanji Brown Jackson (2022) ·
Justices appointed by Trump: 3 ·
Justices appointed by Biden: 1

Quick snapshot

1Confirmed facts
2What’s unclear
  • Whether Congress will ever change the number of justices
  • How individual justices will vote in specific future cases
  • The exact retirement dates of individual justices
  • How future appointments will reshape the Court’s ideological balance
3Timeline signal
4What’s next
  • Potential retirement speculation among older justices
  • Ongoing debate about court expansion in Congress

The nine-justice structure may seem immutable, but a look at the numbers reveals a pattern of change and consolidation.

Category Value
Total Justices 9
Chief Justice John Roberts
Longest Serving Clarence Thomas (since 1991)
Most Recent Ketanji Brown Jackson (2022)
Conservative Justices 6
Liberal Justices 3
The upshot

The 6–3 split is the most lopsided ideological balance since the 1930s, and every major ruling this term reflects that reality.

How many Supreme Court justices are possible?

What is the current number of justices?

The U.S. Supreme Court has exactly nine justices: one Chief Justice and eight Associate Justices, as confirmed by the Supreme Court of the United States.

Has the number always been nine?

No. The Judiciary Act of 1789 established a six-member Court. In 1801 the Midnight Judges Act reduced it to five, but that was quickly repealed. The number fluctuated between six and ten before the Judiciary Act of 1869 fixed it at nine justices.

Can the number of justices be changed by Congress?

Yes. The size of the Supreme Court is set by statute, not the Constitution. Congress has the power to change it by passing a new law, subject to presidential approval. The most famous attempt was Franklin D. Roosevelt’s 1937 court-packing proposal, which failed in the Senate.

Bottom line: The nine-justice Court is a legal choice, not a constitutional requirement. Congress could alter it at any time—but the political cost of doing so has so far prevented any change.

How many justices did Trump add to the Supreme Court?

Which justices did Trump appoint?

President Donald Trump appointed three justices: Neil Gorsuch (joined April 10, 2017), Brett Kavanaugh (joined October 6, 2018), and Amy Coney Barrett (joined October 27, 2020), according to the Supreme Court’s official roster.

How did Trump’s appointments affect the court’s ideological balance?

These three appointments shifted the Court from a 5–4 conservative majority to a 6–3 conservative supermajority. The University of Cincinnati (2025 preview) and CNN both describe the conservative bloc as Roberts, Thomas, Alito, Gorsuch, Kavanaugh, and Barrett.

The implication: Trump’s appointments reshaped American law for a generation, affecting rulings on abortion, gun rights, and executive power.

Who is the Chief Justice of the Supreme Court?

Who is the current Chief Justice?

The current Chief Justice is John G. Roberts, Jr., who joined the Court on September 29, 2005, appointed by President George W. Bush (Supreme Court biographies).

What is the role of the Chief Justice?

The Chief Justice presides over oral arguments, administers the oath to the President at inaugurations, and assigns the writing of majority opinions when in the majority. The Supreme Court’s official site describes the Chief Justice as “the head of the judicial branch of the federal government.”

How is the Chief Justice selected?

Like associate justices, the Chief Justice is nominated by the President and confirmed by the Senate. The position does not require prior service on the Court.

The pattern: The Chief Justice wields significant procedural power, but only one vote among nine. For a comparison with another long-serving leader, see How Long Has Putin Been President? Full Timeline & Term Limits.

Who are the 9 current Supreme Court Justices?

Who are the associate justice?

The nine justices as of 2025 are:

  • John G. Roberts, Jr. – Chief Justice (appointed by George W. Bush, R)
  • Clarence Thomas – appointed by George H. W. Bush (R)
  • Samuel A. Alito, Jr. – appointed by George W. Bush (R)
  • Sonia Sotomayor – appointed by Barack Obama (D)
  • Elena Kagan – appointed by Barack Obama (D)
  • Neil M. Gorsuch – appointed by Donald Trump (R)
  • Brett M. Kavanaugh – appointed by Donald Trump (R)
  • Amy Coney Barrett – appointed by Donald Trump (R)
  • Ketanji Brown Jackson – appointed by Joseph Biden (D)

Each justice serves a life term. The dates of appointment are from Spreme Court of the United States.

How many Supreme Court justices are Republican?

What is the current ideological split?

Six justices are considered conservative (appointed by Republican presidents) and three are liberal (appointed by Democratic presidents), giving the Court a 6–3 conservative majority. CNN and the University of Cincinnati both confirm this alignment.

How is the court’s political leaning determined?

Political leanings are inferred from voting patterns and the appointing president’s party. Justices do not formally affiliate with a party, but their judicial philosophies often align with conservative or liberal ideologies.

The trade-off: While the Court is often described as 6–3 conservative, individual justices can break ranks; Chief Justice Roberts has sided with the liberals in several major cases.

Timeline signal

  • – Judiciary Act of 1789 establishes Supreme Court with 6 justices. (National Archives)
  • – Midnight Judges Act reduces to 5; later repealed.
  • – Judiciary Act sets number at 9 justices. (U.S. Senate)
  • – FDR’s court-packing proposal fails; number remains 9.
  • – Amy Coney Barrett appointed, solidifying 6–3 conservative majority. (CNN)
  • – Ketanji Brown Jackson appointed, first Black woman on the court. (Supreme Court)

Clarity check

Confirmed facts

  • The Supreme Court has 9 justices as of 2025. (Supreme Court of the United States)
  • John Roberts is the Chief Justice. (Supreme Court of the United States)
  • Trump appointed 3 justices. (Justia)
  • The court has a 6–3 conservative majority. (CNN)

What’s unclear

  • Whether the number of justices will change in the future.
  • The exact political leaning of justices in specific cases (often unpredictable).
  • The exact retirement dates of individual justices.
  • How future appointments will reshape the Court’s ideological balance.

“The Court is the highest tribunal in the Nation for all cases and controversies arising under the Constitution or the laws of the United States.”

Supreme Court of the United States (official description)

“The Supreme Court is not a political institution. It’s an institution that has to look at the law and enforce it.”

Chief Justice John Roberts

What to watch

With two justices over 75 and renewed calls for term limits, the nine-justice structure may face its biggest test since 1937. For voters and lawmakers alike, the choice is clear: preserve the status quo or risk a politically charged expansion.

The nine-justice Supreme Court is a product of history, not a constitutional mandate. Its current 6–3 conservative tilt is the result of a single presidential term. For anyone who cares about how American law is shaped, the takeaway is simple: elections have consequences—and the next appointment could tip the balance for decades.

Additional sources

supremecourt.gov, en.wikipedia.org, en.wikipedia.org, constitution.congress.gov, supreme.justia.com, cnn.com, en.wikipedia.org, ceotodaymagazine.com

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Frequently asked questions

Can the number of Supreme Court justices be changed?
How many justices are needed for a majority decision?

At least five justices must agree to form a majority.

Who is the youngest Supreme Court justice currently?

Amy Coney Barrett, born in 1972, is the youngest at age 53 (as of 2025).

Who is the oldest Supreme Court justice currently?
What is the salary of a Supreme Court justice?

As of 2025, associate justices earn about $298,500 and the Chief Justice about $312,200 per year.

How long do Supreme Court justices serve?

They serve life terms during good behavior, with no mandatory retirement age.

How many justices have been impeached?

Only one justice has been impeached: Samuel Chase in 1804. He was acquitted.

What is the difference between the Chief Justice and an Associate Justice?

The Chief Justice presides over the Court and assigns opinions when in the majority, but has one vote just like the others.