NEW SECTION 301 INVESTIGATIONS: WHAT IMPORTERS NEED TO KNOW NOW

TRADE POLICY UPDATE | Prepared By: Rich Fleischer III, LCB | Issued: March 30, 2026

CRITICAL DEADLINE: APRIL 15, 2026

The U.S. government has opened two formal trade investigations that could result in new tariffs on goods from 16 major economies by late July 2026. The window to submit public comments closes April 15, 2026. If your supply chain touches manufacturing goods from China, Mexico, Vietnam, India, or the EU, act before that date. Public comments influence whether tariffs apply to your sector. USTR reviews and considers all submissions before reaching its final determination.

WHAT HAPPENED

USTR launched two formal Section 301 investigations in mid-March 2026, published in the Federal Register on March 17, 2026. These investigations are the administration's direct response to the U.S. Supreme Court's February 20, 2026 decision that struck down the previous IEEPA-based tariffs as unauthorized.

The current 10% global tariff under Section 122 of the Trade Act of 1974, which took effect February 24, 2026, expires after 150 days, on July 24, 2026. USTR has indicated it is working to complete the Section 301 investigations, including proposed remedies, before that expiration. If investigations conclude with a finding of unfair practices, USTR may recommend new tariffs or other trade measures under Section 301.

No new tariffs have been imposed yet. These are investigative proceedings. The comment window is open now.

What is a Section 301 investigation? Section 301 of the Trade Act of 1974 authorizes USTR to investigate foreign trade practices that are unreasonable, discriminatory, or burdensome to U.S. commerce, and to recommend tariffs or other remedies if violations are found. Unlike Section 122 (a temporary global measure capped at 150 days), Section 301 tariffs are targeted, country and sector specific, and have no statutory expiration date.

INVESTIGATION 1: MANUFACTURING OVERCAPACITY (16 ECONOMIES)

USTR is investigating whether 16 economies are engaging in practices related to structural excess capacity and production in manufacturing sectors that unfairly burden U.S. commerce.

What is manufacturing overcapacity? It refers to a situation in which a country produces far more of a product than its domestic market can absorb, then exports the surplus at artificially low prices. This undercuts U.S. producers and distorts global pricing.

Countries Under Investigation: China, the European Union, Singapore, Switzerland, Norway, Indonesia, Malaysia, Cambodia, Thailand, South Korea, Vietnam, Taiwan, Bangladesh, Mexico, Japan, and India.

Sectors of Concern: Aluminum, automobiles, batteries, cement, chemicals, electronics, energy goods, glass, machine tools, machinery, non-ferrous metals, paper, plastics, processed food and beverages, robotics, satellites, semiconductors, ships, solar modules, steel, and transportation equipment.

If your business imports goods in any of these sectors from these countries, this investigation may be relevant to your supply chain planning.

Federal Register: Vol. 91, No. 51, March 17, 2026, Doc. No. 2026-05214. USTR Source | Federal Register Notice

INVESTIGATION 2: FORCED LABOR ENFORCEMENT (60 ECONOMIES)

USTR is separately investigating whether 60 economies are failing to impose and effectively enforce a prohibition on the importation of goods produced with forced labor.

What does 'effective enforcement' mean? USTR is examining whether each country has domestic laws that ban forced-labor-produced goods and whether those laws are being genuinely enforced, not just written on paper.

This investigation covers 60 specific trading partners. The full country list appears in the Federal Register notice. Federal Register Notice (Doc. 2026-05151)

HOW THE TWO INVESTIGATIONS COMPARE

Investigation 1 (Overcapacity): 16 named economies, 21 manufacturing sectors, hearing May 5, 2026.

Investigation 2 (Forced Labor): 60 specific trading partners, all imports from covered countries, hearing April 28, 2026.

Both investigations share the same comment deadline: April 15, 2026, and both are published in Federal Register Vol. 91, No. 51, March 17, 2026.

KEY DATES

April 15, 2026: Public comment deadline for both investigations (hard cutoff).

April 28, 2026: Forced labor investigation hearing, U.S. International Trade Commission, Washington, D.C.

May 5, 2026: Overcapacity investigation hearing.

July 24, 2026: Section 122 global tariff expires; likely timing for any new Section 301 tariffs.

YOUR COMMENT OPPORTUNITY

The comment process is an opportunity for importers and businesses to inform USTR of the real-world impact new tariffs would have on their operations, supply chains, and costs. USTR is required by law to consider all written submissions in its investigation.

To submit written comments: comments.ustr.gov | Deadline: April 15, 2026. To request to appear at a hearing, submit your request alongside your written comments by April 15.

Contact your customs broker or trade attorney to discuss whether submitting comments is appropriate for your situation.

WHAT REMAINS UNRESOLVED

These investigations are in their early stages. As of March 30, 2026, the following are unknown:

Whether USTR will find violations and recommend tariffs, or pursue a negotiated outcome.

Which specific product categories will face tariffs and at what rates.

Whether all 16 or 60 countries will face the same outcome or country-specific treatment.

Whether the Section 122 global tariff will be extended if investigations are not complete by July 24, 2026.

No rates, no product lists, and no tariff actions have been proposed. Richard G. Fleischer Customs Brokers will issue a separate advisory the moment USTR proposes specific remedies.

WHAT YOU SHOULD DO NOW

1. Identify your exposure. If your business imports goods from any of the 16 overcapacity countries in the 21 sectors listed above, or from any of the 60 forced-labor investigation countries, these proceedings affect your supply chain planning.

2. Consider the comment window. Businesses that source goods from affected countries have until April 15 to submit written comments to USTR describing their business reality. Contact your customs broker or trade attorney to discuss whether a comment is appropriate.

3. Mark July 24 on your calendar. This is the likely inflection point. Any Section 301 tariffs resulting from these investigations would be timed around the expiration of the Section 122 tariff.

4. Watch for our next advisory. When USTR announces proposed tariff rates and affected product categories, we will issue a follow-up with specific HTS headings and guidance for your supply chain.

OUR COMMITMENT

Our team is monitoring both dockets in real time and will issue advisories as USTR announces developments. We recommend also monitoring comments.ustr.gov directly to ensure you do not miss updates.

REFERENCES

USTR Press Release: Section 301 Investigations, Structural Excess Capacity - Published March 11, 2026; Federal Register notice March 17, 2026.

USTR Press Release: 60 Section 301 Investigations, Forced Labor - Published March 2026; Federal Register notice March 17, 2026.

Federal Register Doc. 2026-05214 (Overcapacity Investigation) - Vol. 91, No. 51, March 17, 2026.

Federal Register Doc. 2026-05151 (Forced Labor Investigation) - Vol. 91, No. 51, March 17, 2026.

USTR Public Comment Portal - For submitting written comments; search for the relevant docket.

This trade advisory reflects information available as of March 30, 2026. Trade regulations, executive orders, and tariff classifications are subject to frequent change. Nothing herein constitutes legal advice. Richard G. Fleischer Customs Brokers encourages all importers to consult with a licensed customs broker or qualified trade counsel regarding their specific circumstances.