USTR Opens Section 301 Investigations Into 16+ Countries: New Tariffs Possible by Mid-2026
On March 17, 2026, the U.S. Trade Representative formally opened two broad Section 301 investigations targeting manufacturing overcapacity in 16 major economies — including China, Vietnam, Mexico, India, Japan, South Korea, Taiwan, and the EU — and forced labor enforcement failures across 60 countries. Launched directly in response to the Supreme Court's February 20 ruling that invalidated IEEPA tariffs, these investigations are being conducted on an 'accelerated timeline' and could produce new tariff actions by mid-to-late July 2026. If imposed, new Section 301 tariffs would stack on top of the current 10% Section 122 surcharge and existing Section 301 duties, potentially pushing effective rates on China-sourced inventory well above 60%. The public comment window closes April 15, 2026.
Real-World Impact
A product imported from China currently facing ~35% combined duties (25% Section 301 + 10% Section 122) could see rates climb to 60%+ under new Section 301 action — raising a $10 landed cost to roughly $16, adding $6 in import costs per unit before FBA fees.
Key Points
- Two Section 301 investigations launched March 17, 2026: one for manufacturing overcapacity (16 countries), one for forced labor enforcement failures (60 countries)
- Countries under the overcapacity investigation include China, Vietnam, Mexico, India, Japan, South Korea, Taiwan, Germany, Canada, and others
- Investigations replace the IEEPA tariffs struck down by the Supreme Court on February 20, 2026
- USTR has announced an 'accelerated timeline' — potential new tariffs could take effect as early as July 24, 2026
- New Section 301 tariffs would stack on top of Section 122 (10%) and existing Section 301 duties (25%+), potentially pushing effective China rates above 60%
- Public comment deadline: April 15, 2026; public hearings scheduled April 28, 2026 — sellers can formally oppose new tariffs
What You Should Do Now
- 1Submit public comments to USTR before April 15, 2026 — explain how new tariffs would harm your business; formal comments from affected businesses carry weight
- 2Audit your entire supply chain for country of origin — any supplier in the 16-country overcapacity list or 60-country forced labor list may face new tariffs
- 3Begin sourcing diversification planning now — identify alternative suppliers in countries not under investigation
- 4Build worst-case tariff scenarios (up to 60%+ effective rates) into your 2026 and 2027 financial models
- 5Consult a licensed customs broker or trade attorney to verify HTS codes and model potential stacked tariff impacts across your SKUs
- 6Monitor USTR public hearings on April 28, 2026 for early signals on which product categories face the steepest new tariffs