The term tariff stacking has come to refer to the practice of applying multiple import duties and/or tariffs on incoming products.
The term makes no distinction between whether a tariff may have a fixed rate or an ad valorem rate. It’s simply used to refer to when more than one is applied at a time. Therefore, this term could be used to refer to some of the following combinations:
The majority of HTS code designated duties are calculated based on value (ad valorem). The introduction of baseline reciprocal tariffs on nearly all U.S. trading partners is likely to make this the most common tariff stacking situation. Due to the new nature of such practices, it is highly recommended that all importers double check applicable duties and tariffs before import of any product.
See Also: Compound Tariff
Related Articles:
A Guide to U.S. Import Taxes: Duties, Tariffs, and Other Fees
What Are Reciprocal Tariffs? Definition and Purpose
How Do I Find My HTS Code?: Determining Harmonized Tariff Codes

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