The resurgence of Section 301 tariff investigations marks a pivotal shift in U.S. trade policy. Following the Supreme Court’s invalidation of tariffs imposed under the International Emergency Economic Powers Act (IEEPA), the Office of the U.S. Trade Representative (USTR) has turned to Section 301 of the Trade Act of 1974 as a more durable legal pathway to reimpose and potentially expand tariff measures. 

What is Section 301?
Section 301 authorizes USTR to investigate whether foreign governments engage in acts or policies, or practices that are “unreasonable or discriminatory” and that “burden or restrict United States commerce.”[1] If so, the statute empowers the President to “impose duties or other import restrictions… for such time as he deems appropriate.”[2]

Although historically used to pursue disputes through the WTO, Section 301 has evolved into a central enforcement mechanism. Since 2017, it has been used more aggressively to address structural trade concerns, reflecting bipartisan agreement that certain foreign industrial policies undermine U.S. competitiveness.

How Section 301 is Being Used Today
In March 2026, USTR initiated two sweeping investigations that significantly expand the scope of Section 301.

The first targets structural excess capacity across 16 major economies, including China, the European Union, Japan, India, and Mexico.[3] USTR is examining whether foreign governments maintain production levels “untethered from the incentives of domestic and global demand,” often through subsidies, state-owned enterprises, and wage suppression, leading to “overproduction and large or persistent trade surpluses[4].” 

These practices are viewed as directly harmful to U.S. industry. USTR notes they “maintain capacity and production well above what would be expected under more market-oriented conditions,”[5] and may “displace existing U.S. domestic production or prevent investment and expansion… that otherwise would have been brought online.”[6]

The second investigation addresses forced labor enforcement, examining whether approximately 60 trading partners have failed to adopt or effectively enforce prohibitions on imports made with forced labor.[7] USTR emphasizes that such practices distort competition by lowering production costs and undermining fair market conditions.

Both investigations rely on Section 301’s broad standard, which permits action against practices that are “unreasonable… [or] otherwise unfair and inequitable,” and that burden U.S. commerce.[8] Together, they reflect a more expansive theory of actionability that extends beyond traditional tariff barriers to systemic economic and labor practices.

Section 301 vs. IEEPA Tariffs
The distinction between Section 301 and IEEPA is both procedural and legal. IEEPA tariffs relied on emergency powers and were struck down by the courts. Section 301, by contrast, requires a formal process such as investigations, consultations, and public participation, and is specifically designed “to address unfair foreign practices affecting U.S. commerce.”[9] This framework provides greater legal durability while preserving executive flexibility.

Implications for Importers and Next Steps
The implications for importers are immediate. Tariffs resulting from these investigations could take effect as early as mid-2026, particularly as the administration seeks to align outcomes with the expiration of temporary Section 122 tariffs in July.

The Section 301 process also creates opportunities for engagement. The statute requires that USTR “provide an opportunity for the presentation of views,”[10] and the current investigations include public comment and hearing procedures. Key deadlines include:

• April 15, 2026: Deadline for written comments and requests to appear at hearings 
• May 5, 2026: Public hearings held at the US International Trade Commission. 
• Post-hearing submissions: Due within seven days after hearings conclude

Engagement in this process can influence tariff scope, exclusions, and broader policy decisions.

Looking Ahead
Ultimately, the renewed use of Section 301 reflects a broader shift toward assertive trade enforcement. While legal challenges are expected, the statute’s broad delegation of authority and historical judicial deference provide a strong foundation. At the same time, the unprecedented scope of these investigations may invite closer scrutiny.

For businesses, the takeaway is clear: higher tariffs are likely, and active participation in the Section 301 process is essential. Increasingly, Section 301 is being employed not merely as a legal tool, but as a central pillar of U.S. economic strategy.