How to Calculate Duties and Taxes on Imports to US is a critical process for any international business, and the rules have changed significantly in 2025. Import duties and taxes are determined by the product's classification (HTSUS code), its customs value, and its country of origin. Effective August 29, 2025, the U.S. Customs and Border Protection (CBP) suspended the $800 de minimis exemption for commercial shipments, meaning the duty and tax de minimis threshold is now effectively $0 USD. This change requires all commercial imports to undergo full customs clearance and be subject to applicable duties and fees.
Import duties in the US are calculated based on the Harmonized Tariff Schedule of the United States (HTSUS), a 10-digit import classification code maintained by the U.S. International Trade Commission (USITC). The HTSUS code determines the General Rate of Duty. However, in 2025, importers must also account for new 'reciprocal tariffs' and other special duties (like Section 232 or 301 tariffs) which can significantly increase the final rate. These new tariffs impose a baseline 10% additional duty on most imports, with country-specific rates ranging up to 100% or more, depending on the country of origin and product type.
To accurately calculate import tax in US and the total landed cost, importers must follow a multi-step process that begins with classification and valuation. The primary customs valuation basis for general duties is the Transaction Value, which is the price actually paid or payable for the merchandise when sold for export to the United States. This is generally a Free On Board (FOB) equivalent, but the specific dutiable value can exclude certain costs like international freight and insurance, provided they are separately identified.
However, a critical update for 2025 is that the new reciprocal tariffs are explicitly calculated on the Free on Board (FOB) value of the goods, meaning shipping and insurance costs are excluded from the duty calculation for these specific tariffs. This distinction is vital when using an import tax calculator US to estimate the final cost.
In addition to duties, importers must pay federal fees. The two most common are the Merchandise Processing Fee (MPF), calculated at 0.3464% of the declared value (with a minimum of $31.67 and a maximum of $614.35), and the Harbor Maintenance Fee (HMF), calculated at 0.125% of the shipment value for ocean freight. Since the de minimis rule is suspended, these fees apply to virtually all commercial shipments. The entire process of filing and payment is managed through the Automated Commercial Environment (ACE) system, the mandatory platform for all U.S. customs filings.
Determine the 10-digit HTSUS Code: Accurately classify your product using the Harmonized Tariff Schedule of the United States (HTSUS) to find the base duty rate and identify any special tariffs (e.g., Section 232, 301, or the new reciprocal tariffs).
Establish the Customs Valuation: Determine the Transaction Value (price paid/payable) of the goods. Use this value to calculate the Merchandise Processing Fee (MPF) and Harbor Maintenance Fee (HMF). For the new reciprocal tariffs, use the FOB value.
Calculate the Total Duty: Multiply the dutiable value by the applicable HTSUS General Rate of Duty. Then, add any special duties (like the 10% baseline reciprocal tariff or higher country-specific rates) to determine the total customs duties in US.
Calculate Total Import Fees: Add the total duty amount to the mandatory federal fees (MPF and HMF) to find the total import tax calculator US estimate for the shipment. State and local sales taxes may apply post-importation.
Shipment Value Under $800: A commercial shipment valued at $500 USD is no longer exempt. It is subject to the full customs clearance process, applicable duties (e.g., the 10% baseline reciprocal tariff), MPF, and HMF.
Trade Agreement Exemption: Goods qualifying under a Free Trade Agreement, such as the United States-Mexico-Canada Agreement (USMCA), may still be exempt from the General Rate of Duty and the new reciprocal tariffs, provided the correct Certificate of Origin is filed via the ACE system.
International Postal Shipment: Shipments sent through the international postal network are subject to special duty rates, which may be assessed using a specific duty methodology ($80 to $200 per item) for a six-month period, rather than the standard ad valorem duty.
Assuming the $800 De Minimis Still Applies: The most critical mistake in 2025 is assuming commercial shipments under $800 are duty-free; they are not, and failure to declare can lead to penalties.
Incorrect HTSUS Classification: Using an incorrect 10-digit HTSUS code can result in paying the wrong duty rate, leading to CBP penalties or overpayment.
Miscalculating Dutiable Value: Failing to correctly separate the FOB value (for reciprocal tariffs) from the Transaction Value (for general duties and fees) will result in an inaccurate calculation of how import duty is calculated in US.
The 2025 trade landscape is defined by the suspension of the Section 321 de minimis and the implementation of new reciprocal tariffs. Importers must also be aware of the ongoing modernization of the Automated Commercial Environment (ACE 2.0), which mandates real-time data sharing and strict compliance. Furthermore, goods entering a U.S. Free Trade Zone (FTZ) that are subject to the new duties must be admitted under 'privileged foreign status' to manage duty liability.
The de minimis threshold for commercial shipments is $0 USD, as the $800 exemption (Section 321) was suspended on August 29, 2025. All commercial imports are now subject to duties and taxes.
The HTS code is the 10-digit Harmonized Tariff Schedule of the United States code. It is the legal classification for your product and is the primary factor used to determine the applicable duty rate and any special tariffs.
The US does not have a national Value Added Tax (VAT) or Goods and Services Tax (GST). Instead, federal import fees include the Merchandise Processing Fee (MPF) and the Harbor Maintenance Fee (HMF). State and local sales taxes may apply after importation.
The general customs valuation basis is the Transaction Value (price paid/payable). However, the new reciprocal tariffs implemented in 2025 are calculated specifically on the Free on Board (FOB) value of the imported goods.