US Import Tariff Guide for Product Businesses (2025)

Import tariffs are one of the most significant and most misunderstood costs in product importing. Get them wrong and your margin calculations are off from the start. This guide covers everything a manufacturer or importer needs to know about US import tariffs in 2025 — including MFN rates, Section 301 China tariffs, how to find your HTS code, and how to factor duties accurately into your pricing.

How US Import Tariffs Work

When goods enter the United States, US Customs and Border Protection (CBP) assesses import duties based on two factors: the product's classification under the Harmonized Tariff Schedule (HTS) and the country of origin. The duty is calculated as a percentage of the customs value — typically the FOB (Free on Board) value of the goods.

Most countries trade with the US under MFN (Most Favored Nation) rates, which are the standard tariff rates applied to all WTO member countries. These rates vary widely by product category — from 0% on many industrial goods to 37.5% on some footwear and apparel.

Section 301 China Tariffs

Since 2018, products manufactured in China have been subject to additional Section 301 tariffs on top of the standard MFN rate. These tariffs were introduced in four tranches and cover the vast majority of Chinese-manufactured goods:

• List 1 (July 2018): 25% additional tariff on ~$34B of goods (industrial machinery, electronics components)
• List 2 (August 2018): 25% additional tariff on ~$16B of goods (semiconductors, chemicals)
• List 3 (September 2018, increased May 2019): 25% additional tariff on ~$200B of goods (consumer electronics, furniture, apparel)
• List 4A (September 2019): 7.5% additional tariff on ~$120B of goods (consumer products, clothing, footwear)

As of 2025, these tariffs remain in effect. The combined rate for a product subject to List 3 with a 5% MFN rate would be 30% total. For a product with a 0% MFN rate subject to List 4A, the total rate is 7.5%.

Important: Section 301 tariffs are calculated on the same customs value as MFN duties — they stack on top of each other, they are not applied to the duty-inclusive value.

How to Find Your HTS Code

The HTS (Harmonized Tariff Schedule) code is a 10-digit classification number that determines your duty rate. The first 6 digits are internationally standardized (the HS code); the last 4 digits are US-specific.

To find your HTS code:

1. Visit hts.usitc.gov — the official US International Trade Commission HTS lookup tool.
2. Search by product description or browse the chapter that covers your product category.
3. Identify the 10-digit code that most precisely describes your product.
4. Check the "General" column for the MFN rate and any "Special" column entries for preferential rates (USMCA, etc.).
5. Check for any Section 301 additional duties in the "Additional U.S. Notes" section.

If you are unsure of your classification, consult a licensed customs broker. Misclassification can result in penalties, back-payment of duties, and delays at the border. For large or recurring shipments, consider a binding ruling from CBP — it gives you legal certainty on your classification.

Country of Origin Rules

The country of origin determines which duty rate applies. For most products, the country of origin is where the product was substantially transformed — not where it was assembled or packaged.

This matters for manufacturers who source components from China but assemble in Vietnam, Mexico, or another country. If the assembly in the third country constitutes a substantial transformation (i.e., the product becomes a fundamentally different article), the country of origin may shift — potentially reducing or eliminating Section 301 tariffs.

CBP has strict rules on what constitutes substantial transformation, and there have been significant enforcement actions against companies attempting to circumvent Section 301 tariffs through minimal processing in third countries. If you are considering this approach, get a binding ruling from CBP before committing to the supply chain change.

USMCA and Other Preferential Programs

Products manufactured in Canada or Mexico may qualify for 0% duty under the USMCA (United States-Mexico-Canada Agreement), provided they meet the rules of origin requirements. This can be a significant advantage for manufacturers with North American supply chains.

Other preferential programs include the Generalized System of Preferences (GSP) for qualifying developing countries — though GSP has lapsed and been renewed multiple times and its status should be verified at the time of import.

Calculating Your Duty Cost Per Unit

The formula is straightforward:

For example: a product with a $10 FOB value, 5% MFN rate, and 25% Section 301 tariff:

This $3.00 is a direct addition to your landed cost. On a product selling for $25, that is 12% of your sale price going to duties alone — before freight, fees, or any other cost.

First Sale Valuation

For manufacturers who buy from a factory and sell through a middleman, "first sale" valuation allows you to declare the factory price (not the middleman price) as the customs value — potentially reducing your duty basis. This requires documentation of the entire supply chain and is subject to CBP approval, but can result in meaningful duty savings on large volumes.

Duty Drawback

If you import goods that are subsequently exported, you may be eligible for duty drawback — a refund of up to 99% of duties paid on the imported goods. This is particularly relevant for manufacturers who import components, process them, and export finished goods. Duty drawback programs are administered by CBP and require detailed record-keeping.

Building Tariffs Into Your Pricing

The most important practical takeaway: tariffs must be included in your landed cost calculation before you set any prices. A product with a 30% combined tariff rate that you are pricing based on the pre-tariff cost is a product with a margin that is 30% smaller than you think.

Use a tool that automatically calculates tariff costs based on country of origin and product category, and includes them in your landed cost and all downstream margin calculations. Manual spreadsheet updates are error-prone and often out of date.