The International Emergency Economic Powers Act (IEEPA), 50 U.S.C. §§ 1701–1708, authorizes the President to regulate international commerce in response to an "unusual and extraordinary threat" originating substantially outside the United States, after declaring a national emergency under the National Emergencies Act.
IEEPA has historically been used to impose sanctions (asset freezes, transaction bans), not tariffs. In 2025, the Trump administration broke from that pattern by invoking IEEPA to impose:
- Fentanyl tariffs — 10–25% tariffs on imports from China, Canada, and Mexico, citing the opioid crisis as the predicate emergency (Executive Orders 14193, 14194, 14195)
- Reciprocal tariffs — Country-specific tariffs ranging from 10% to over 50% imposed in April 2025, citing chronic U.S. trade deficits as a national emergency (Executive Order 14257)
Both programs were declared under Chapter 99 of the HTSUS, primarily in the 9903.01 subheading range.
The legal basis was promptly challenged. In V.O.S. Selections, Inc. v. Trump and Trump v. CASA, federal courts found that IEEPA does not authorize across-the-board tariffs, holding that the statute's reference to regulating "importation" was not intended to authorize what amounts to a general taxing power. The litigation produced injunctions and refund obligations on certain entries during 2025, prompting the administration to backstop policy with Section 122 and to file petitions under Section 301.
As of 2026, IEEPA-based tariffs remain in flux. Some IEEPA duties continue under narrower theories tied to specific threats (fentanyl flows, sanctions-related conduct), while broader reciprocal tariff coverage has migrated to Section 301 or Section 232 authorities where available.