What is Tariff Stacking, and How Does it Affect Importers?

Since early 2025, duty and tariff calculations in the United States have grown in complexity due to the implementation of several new tariffs on foreign trade partners. On some commodities, these tariffs overlap and create an instance of tariff stacking, which is the application of multiple tariffs to a single type of commodity. 

Key Takeaways

• Tariffs on goods imported into the United States can stack based on factors like the commodity, its constituent materials, and country of origin.
• Articles of steel, aluminum, and copper  sourced from China are among those commodities most prone to tariff stacking.
• Tariff rates and the rules that determine how they stack can change as new trade agreements, executive actions, and sectoral investigations happen.
• United States Customs and Border Protection (CBP) offers guidance to importers on how to determine which tariffs stack, but stress that the obligation is upon the importer or their broker to estimate and pay the correct customs fees per shipment.

In this article, I’ll explain how tariff stacking works, provide a common tariff stacking scenario importers face, and discuss legal methods to mitigate this issue.

USA CUSTOMS CLEARANCE

Take on Tariff Turmoil With Help From Experts in Customs Brokerage

Our 45 Minute Licensed Expert Consulting Will Personally Guide You.

Contact our Licensed Expert Consultant >

Tariff Stacking: Key Terms and Definitions

Tariff stacking refers to multiple tariffs simultaneously being applied to a single commodity. When several of these levies are stacked together, they are often referred to as a cumulative tariff. 

In early 2025, the executive branch of the United States federal government began levying multiple types of tariffs specific to factors like country of origin, commodity classification, and calculations based on trade deficits with other countries.

To gain a more complete understanding of how customs charges can stack, let’s look at some of the different types of import taxes countries use.

• General Rates of Duty: Duties are usually assessed based on the value or weight of goods imported. They are listed in the Harmonized Tariff Schedule. 
• Anti Dumping/Countervailing Duties (AD/CVD): Tariffs imposed by the US on goods from countries or suppliers who are suspected of selling products under market value to damage the domestic economy. 
• Ad Valorem Tariff: Meaning “according to value”, it describes a tariff or duty that is assessed as a percentage of an item’s cost.
• Specific Tariff: Tariffs expressed as a set monetary value per unit, contrasting with ad valorem’s percentage-based determination.
• Sectoral Tariff: These are levied on specific goods regardless of country of origin. A modern example is the 25% vehicle tariff applied to most nations.
• Compound Tariff: A combination of ad valorem and specific tariffs.
• Reciprocal Tariffs: These are imposed in response to another country’s tariffs or non-tariff trade barriers. In the US, they are sometimes called IEEPA reciprocal tariffs since they’re based on powers enumerated by the International Emergency Economic Powers Act.
• Section 301 Tariffs: Additional trade levies imposed in accordance with Section 301 of the Trade Act of 1974.
• Section 232 Tariffs: These can be applied according to rules set forth in Section 232 of the Trade Expansion Act of 1962. 

Many of these rates can be reduced or eliminated by free trade agreements such as the United States-Mexico-Canada Agreement (USMCA). 

Now that we’ve defined these different types of tariffs, let’s look at some examples of how they might stack on top of each other.

Related: A Comprehensive Guide to Section 232 Tariffs

How Tariff Stacking Works

To illustrate how multiple tariffs can stack on a single commodity, let’s look at auto parts sourced from China. Between IEEPA, sectoral ,and commodity-specific tariffs, commercial importers in the US have seen triple digit effective tariff rates on numerous Chinese goods.

In this scenario, you’ll see a common and relatively uncomplicated instance of tariff stacking: Section 232 auto part tariffs and those assessed on China via IEEPA. Keep in mind these duty and tariff calculations are each based on the original shipment value. 

This amounts to an increase of 47.5% over initial costs. Keep in mind that these rates can change quickly during times of high tension in international trade. As always, the burden of tariff and duty calculation is on the importer, and you’ll need to thoroughly research your intended purchase from a commodity and even supplier level to ensure your calculations are accurate. 

Partnering with a licensed customs broker can eliminate a great deal of this headache.

Related: Importing Auto Parts Into the U.S.

Can I Avoid Tariff Stacking?

Tariff stacking can be difficult to avoid. However, it can be mitigated by sourcing your products from countries with whom the USA shares an FTA or other trade agreement. 

Free trade partners with the US receive preferential rates of duty, and sometimes no duty at all.   Some trade deals agreed upon in 2025 didn’t completely eliminate tariffs, but did reduce their effective rates. 

So, if you have a choice of sourcing goods from a trade partner that has negotiated an agreement with the United States and a country subject to high, unmodified import tax rates, you’ll pay less overall in import taxes from the former. 

The best way to make sure you don’t pay more in import fees than necessary is to have a licensed customs broker handle the clearance process on your behalf. 

Minimize Your Tariff Costs With USA Customs Clearance

The brokers and customs experts at USA Customs Clearance have over a century of combined experience helping import businesses cut through the red tape of the clearance process. Additionally, they can put their knowledge to work by helping you mitigate tariff costs on imported goods.
Don’t let tariff turmoil tear down your business. Call us at (855) 912-0406 or submit a contact form online today!