Base Tariffs vs. Additional Tariffs During the Transitional Phase

However, a transitional period was soon agreed to facilitate negotiations. On April 9, 2025, the US suspended the country-specific supplemental tariffs for 90 days; the universal base tariff of 10% remained in effect. For Switzerland, this meant that instead of the threatened total tariff rate of 31%, only 10% was temporarily applied.

Base tariff of 10%

Before April 5 (i.e., up to April 1), there was no universal 10% base tariff. Only the existing tariffs applied, such as the Section‑232 steel and aluminum penalty tariffs, where relevant.

39% Penalty Tariff from August 7, 2025

Cumulative in the strict sense (i.e., 10% + 39% = 49%) does not apply here; instead, the 39% rate now applies to Swiss products. The 10% from the transitional phase was replaced by the higher rate and is not added. However, this tariff is in addition to all other duties (MFN tariffs, antidumping, countervailing duties, and taxes), except where exemptions or trade agreements apply. The following exemptions exist:

• Annex II of Executive Order 14275 (April 2, 2025): Semiconductors, pharmaceuticals, and high-tech electronics, listed by tariff number. The Presidential Memorandum of April 11 expands exemptions to integrated circuits, smartphones, SSDs, flat panel modules, and monitors.
• Exceptions according to Section 232: Valid for steel, aluminum, vehicles and components, copper. These do not stack with reciprocal tariffs under Executive Order 14257.

These examples show that the USA has set different total tariff rates depending on the country.

Sector-Specific Tariffs: Autos, Copper, Aluminum, Steel

• Auto tariffs: The Trump administration implemented an additional tariff of 25% on imported vehicles and parts for security reasons (Section 232). This is in addition to the general tariff. For example, the regular US MFN tariff for passenger cars is 2.5%. The 25% penalty tariff is cumulative, so in total 27.5% tariff is levied on cars.

During recent trade talks, it became clear that the USA wanted to treat auto tariffs separately from general country tariffs. In the case of the EU, an agreement integrated autos into the 15% total tariff, avoiding double charges. For other countries without special agreements, auto tariffs could be added to the country tariff.

• Copper tariffs: In early July 2025, President Trump announced a 50% penalty tariff on copper imports, effective August 1, applicable to all origin countries not specifically exempted.
• Aluminum and steel tariffs: Since 2018, the US under Trump has levied special tariffs on steel and aluminum (Section 232 measures). The original rates are 25% on steel and 25% on aluminum for almost all supplying countries, including Switzerland. These tariffs have been in addition to regular tariffs from the start. These 50% are also cumulative to the MFN.

For example, European exporters, despite a trade agreement, had to pay 50% on steel and aluminum, in addition to the agreed 15% general tariff on other goods.

Current Status and Other Products With Special Tariffs

• Chinese goods: Since 2018, the Trump administration has imposed supplemental tariffs (Section 301 measures) on imports from China. In Trump's second term, these were further increased. In April 2025, the US raised penalty tariffs on China by another 50 percentage points to a total of 104%. This is a cumulative total, reached by stacking several tariff rounds (a huge burden, which China responded to with retaliatory tariffs). The last China tariff round remains paused at 30% for now; Mexico and India also received postponements or additional tariffs.

China is an extreme example: different penalty rounds stack, showing clearly that each new round is added to the previous ones. Only a new framework agreement between the USA and China in June 2025 brought some relief, but high tariffs remain in place for now.

• Washing machines and solar panels: Since 2018, global safeguard tariffs (Section 201) on washing machines and solar panels have been levied in addition to existing tariffs.
• Pharmaceuticals: So far, drugs and many high-tech components are exempt from the new penalty tariffs, partly due to concerns over negative impacts. However, in July 2025, President Trump threatened up to 250% tariff on pharmaceutical products after a grace period. This would be another separate penalty tariff.
• A similar announcement came for semiconductors/chips from certain countries (e.g., Taiwan) in early 2025. These threats are not fully implemented yet, but they illustrate the US approach to imposing targeted penalty duties on further sectors.

Tariffs on Circumvention

Stacking as a Core Term – Summary and Conclusion, As of 08.08.2025:

• The MFN rate remains in effect. Agreements may lift it:

  • Base rate of 10% is replaced by reciprocal tariff (e.g., 39%).

  • In some agreements, the reciprocal tariff serves as a cap (e.g., EU: base 15%): If standard tariff < 15%, reciprocal tariff supplements up to 15%. If standard tariff > 15%, only the standard rate applies, no reciprocal tariff.

  • China surcharges (China IEEPA Fentanyl) apply additionally for Chinese origin, not for reciprocal China IEEPA tariffs.
  • "AD/CV duties" remain:

    • AD duties = Anti-Dumping Duties → Penalty duties on goods sold below fair market value.

    • CV duties = Countervailing Duties → Duties on goods receiving unfair subsidies in the export country.

In the context of Section 232 and IEEPA:

• Tariff number checks must currently be performed manually, including by customs agents; a CW1 software is planned to automate data matching in the future.

  • In some agreements not cumulative with reciprocal tariffs (e.g., USMCA), depending on the agreement.

  • If no agreement: new rule “stacking” determines what is cumulative.

  • Aluminum and steel tariffs can be levied simultaneously.

  • China IEEPA (Fentanyl tariffs) are also levied here, but not reciprocal China IEEPA tariffs.
  • These surcharges are not additionally levied on goods affected by the "Vehicles" directive (Section 232).
  • IEEPA country-specific tariffs do not apply under this section.
  • Anti-dumping/countervailing duties, Section 301 etc. apply here as before.

    50% duty on steel/aluminum (Section 232)

• Conclusion: Situation unclear: No central US Customs directive.

  • Sources: Tariff schedule (standard tariff, Section 301), CSMS (Section 232, IEEPA), FAQ sites, Federal Register, Executive Orders.

  • Problem: scattered, partially contradictory information, no consistent methodology.

   

When Are Tariffs Cumulative – and Why?

Once the deadline expires or negotiations fail, the higher penalty tariff takes effect and replaces the interim rate (e.g., Switzerland from 10% to 39%). In bilateral deals, it can be agreed that certain sector tariffs are exempted or included in the total tariff. Example: In the US-EU agreement, autos were included in the 15% total tariff, while steel/aluminum were explicitly excluded (still 50%). Such arrangements prevent double charges in some areas, but are politically negotiated and not the norm. In this agreement, all reciprocal tariffs are added to any existing MFN rate, unless already at 15% (ceiling), except for sector-specific tariffs.