On April 2, 2026, the President of the United States signed a new Proclamation modifying the tariff framework applicable to imports of steel, aluminum and copper and their derivative products, under Section 232 of the Trade Expansion Act of 1962,  effective as of April 6, 202..  

The measure introduces significant changes to the determination of the tax base, as well as to applicable tariff rates, reinforcing the protection of U.S. domestic industry. 

Key aspects: 

1.- Previoustariff regime.  

Since 2025, United States has applied tariffs under Section 232 to imports of steel, aluminum, and copper, including—since July of that year—an additional 50% tariff on the value of the copper content in imported semi-finished and derivative products. 

2.- Key amendments to the existing tariff framework. 

a) Change in tariff calculation base

The Proclamation establishes that tariffs will now be applied to the total value of the imported product, rather than being limited to the value of its metal content. This change significantly broadens the tax base and increases the effective tariff burden. 

b) New differentiated tariff rates
A tiered system of differentiated tariff rates is introduced based on metallic content, industrial use and origin of inputs: 

• 50% for products manufactured entirely or almost entirely from steel, aluminum or copper. 
• 25% for derivative products with substantial metal content (i.e., steel coils and aluminum sheets). 
• 15% for certain metal-intensive industrial equipment and power grid equipment (effective until 2027). 
• 10% for products manufactured abroad but made entirely from U.S.-origin metal inputs.  

Products with metal content equal to or below 15% are excluded from tariffs under this regime. 

3.- Refined copper: potential future regulation

The Proclamation does not addressany changes with respect to refined copper. However, prior statements by the U.S. government remain in effect, and it is expected that, before June 30, 2026, the Secretary of Commerce will issue a report regarding the potential phased imposition of tariffs on this product (15% starting in 2027 and 30% starting in 2028). 

Practical impact for Chile 

For Chilean exporters, this new framework generally results in a higher tariff burden in the U.S. market, particularly for products with higher non-metallic added value. 

However, the actual impact will depend on factors such as metal content, product use and origin of inputs. Accurate product classification and technical characterization will be essential to determine the applicable tariff and manage regulatory exposure.