How to Calculate US Import Duty: The 2025 Step-by-Step Guide (Includes Free Calculator)

Importing into the United States in 2025 is more complex—and more costly—than ever before.

For years, many e-commerce sellers and small importers relied on an $800 "De Minimis" loophole to ship goods to US customers tax-free. As you've likely discovered, that era is over.

With the recent suspension of the De Minimis rule (Section 321), every shipment, no matter how small, is now potentially subject to tariffs. When you combine this with the complex, multi-layered Section 301 tariffs on goods from China, one thing becomes clear: you can no longer afford to guess.

Relying on an old spreadsheet or a "general rule of thumb" is now the fastest way to lose your profit margin, delay your shipments, and anger your customers.

The good news? You don't have to guess. This guide will provide the step-by-step process for calculating US import duties and, more importantly, introduce a free tool to do it for you instantly.

Why Accurate Duty Calculation is Critical in 2025

Before we get to the "how," let's understand the "why." If your calculations are wrong, you face serious consequences:

• Lost Profitability: You quote a price to your customer, only to find the actual duty is 25% higher than you expected, wiping out your entire margin.
• Seized Goods & Delays: US Customs (CBP) will hold your shipment if the declared value or calculated duty is incorrect, leading to weeks of delays.
• Angry Customers: Nothing ruins a customer experience faster than receiving an unexpected "bill" from the courier for customs fees they thought were already paid.
• Legal Penalties: Repeatedly miscalculating duties can lead to fines and penalties from CBP.

The game is no longer just about logistics; it's about financial precision.

The 5 Steps to Manually Calculate US Import Duty

Here is the traditional, manual process for calculating your duties. (Warning: It's complicated, which is why we built the calculator.)

Step 1: Find Your HTS Code

This is the most important step. The Harmonized Tariff Schedule (HTS) code is a 10-digit number that US Customs uses to classify every single product imaginable. This code determines everything that follows.

Example: A men's cotton t-shirt might be 6109.10.0040.

Why it's hard: The HTS database is massive and complex. Classifying a simple product like a "wireless earbud" can be confusing. Is it an audio receiver? A plastic good? An electronic part? Getting this wrong is the first and most common mistake.

Step 2: Determine Your Customs Value

You don't pay duty on the sales price of your product. You pay duty on the Customs Value. For the US, this is typically the "FOB" (Free on Board) value—essentially, the price you paid for the goods, not including shipping and insurance.

Example: You buy 100 t-shirts for $500 and pay $100 for shipping. Your Customs Value for the shipment is $500.

Step 3: Find the Base Duty Rate

Once you have your HTS code, you can look up its "General" duty rate in the official HTS database.

Example: The HTS code 6109.10.0040 (men's cotton t-shirt) has a "General" duty rate of 16.5%.

So, your calculation would be: $500 (Value) * 16.5% = $82.50.

Easy, right? Wrong. This is where 90% of importers make a critical error. You must now check for additional duties.

Step 4: Check for Additional Tariffs (Section 301, ADD/CVD)

This is the step that makes manual spreadsheets impossible. Your product may be subject to multiple other tariffs stacked on top of the base rate.

• Section 301 (China Tariffs): If that t-shirt was "Made in China," it is likely subject to an additional Section 301 tariff. This rate could be 7.5%, 15%, or even 25% on top of the 16.5%.
• Antidumping/Countervailing (ADD/CVD): If the US determines a country is "dumping" products (selling below market cost), it will apply massive ADD/CVD duties, which can be over 200%.

Step 5: Do the Final Math

Let's say your cotton t-shirt from China is subject to an additional 7.5% Section 301 tariff.

Base Duty: $500 * 16.5% = $82.50
Section 301 Duty: $500 * 7.5% = $37.50
Total Duty Owed: $82.50 + $37.50 = $120.00

Your actual duty rate isn't 16.5%; it's 24%. If you only calculated for the base rate, you would have just underpaid by 31%.

The Better Way: Use a Free Calculator

Feeling overwhelmed? You should be. This manual process is slow, risky, and prone to human error.

This is exactly why we built the US Import Duty Calculator.

Instead of digging through government websites and managing complex spreadsheets, our tool simplifies this entire 5-step process into one click. It's designed to give you an instant, accurate, and reliable calculation so you can protect your profits and serve your customers.

How it works:

• Enter Your HTS Code: Input the 10-digit code for your product.
• Enter Your Value: Type in the Customs Value of your shipment.
• Get Your Result: The calculator automatically computes the total landed cost, including the base rate and any applicable Section 301 or other duties.

No more guessing. No more spreadsheets. Just a single, accurate number you can build your business on.

Frequently Asked Questions (FAQ)

Q: What happened to the $800 De Minimis rule?

A: As of late 2025, the Section 321 "De Minimis" rule, which allowed shipments under $800 to enter the US tax-free, has been suspended for many carriers and shipment types. This means almost all low-value goods are now subject to duties, making accurate calculation essential.

Q: What is the difference between Section 301 and regular tariffs?

A: Regular tariffs (the "General" rate) apply to goods from almost all countries. Section 301 tariffs are a specific, additional trade remedy tax currently applied to thousands of products imported from China. Our calculator automatically includes these where applicable.

Q: Where can I find my HTS code?

A: Your product supplier or manufacturer should be able to provide you with the correct HTS code. You can also use the official US International Trade Commission HTS search tool, though it can be difficult to navigate.