The record

LegislationLegislation· Jul 2025
S 331 Signed into law

Sponsored by Bill Cassidy (R)

HALT Fentanyl Act

Permanently schedules fentanyl-related substances as controlled drugs and streamlines research registration.

Tradeoff

Treats all fentanyl variants as Schedule I controlled substances with the same criminal penalties as fentanyl itself. Simplifies registration and inspection requirements for researchers studying Schedule I drugs.

What's in it

See official bill text

Adds less than $500,000 to federal spending over 2025-2030 for enforcement and ; negligible net deficit impact over 10 years.

The $500,000 federal cost is just the administrative expense for DOJ to write rules and report to Congress—the policy's real impact is on drug traffickers (who face stricter criminal liability) and researchers (who face new registration requirements), not on the federal budget.

S. 331, HALT Fentanyl Act · Mar 2025

The Senate agreed to advance the bill on March 6, 2025 by (82-12). The Senate voted again on March 13 (84-15) and passed the bill 84-16 on March 14, 2025. The House passed it 321-104 on June 12, 2025, and it was signed into law.

  1. Senate

    Introduced

    (Jan 30, 2025)

  2. Senate

    Committee on the Judiciary(Jan 30, 2025)

  3. Senate

    The Committee on the Judiciary voted to send it to the floor

    Reported(Feb 27, 2025)

  4. Senate

    On on the

    Motion to Invoke Cloture: Motion to Proceed to S. 331

    Cloture on the Motion to Proceed Agreed to(Roll #110 · Mar 6, 2025)

    82 yeanay 12

  5. Senate

    On the Motion

    Motion to Invoke Cloture: S. 331

    Cloture Motion Agreed to(Roll #124 · Mar 13, 2025)

    84 yeanay 15

  6. Senate

    Passage of the bill

    S. 331, as amended

    Bill Passed(Roll #127 · Mar 14, 2025)

    84 yeanay 16

  7. House

    Received from the Senate

    Received(Mar 18, 2025)

  8. House

    Passage of the bill

    Passed(Roll #166 · Jun 12, 2025)

    321 yeanay 104

  9. House

    Sent to the President

    (Jul 8, 2025)

  10. White House · Signature

    Signed

    Donald Trump (R)

  11. Enacted

    Became law(Jul 16, 2025)

Final passage· 119th Congress · 2025–2027