US Import Requirements: The Complete Guide

US import requirements are the legal rules every importer must satisfy to bring goods through US Customs and Border Protection (CBP) and into domestic commerce. Getting them right determines whether your shipment clears in hours or sits in a warehouse for weeks.

For any business importing goods commercially into the United States — whether that’s 10 units or 10,000 — understanding the full compliance picture is not optional. CBP processed over 36 million formal entry summaries in fiscal year 2023, collecting more than $80 billion in duties, taxes, and fees. Behind every cleared shipment is a chain of documentation, classification, valuation, and agency approvals that must be handled correctly before cargo is released.

What “US Import Requirements” Actually Means

Customs Entry: A formal import entry is the legal declaration filed with CBP that identifies who is importing goods, what those goods are, where they came from, what they are worth, and how much duty is owed. It is required for any commercial shipment with a value above $2,500 under 19 USC 1484.

Import requirements span five core areas:

1. Classification — assigning an HTS code that determines the duty rate
2. Valuation — declaring the correct customs value under 19 CFR Part 152
3. Documentation — commercial invoice, packing list, bill of lading or airway bill, and entry forms
4. Admissibility — meeting any agency rules from FDA, USDA, EPA, CPSC, or other regulators
5. Duty payment — paying all applicable tariffs, fees, and any trade remedy duties

Every shipment must satisfy all five areas. A shipment can have a perfect customs entry and still be detained because it lacks an FDA prior notice for food imports. Compliance is not a single checkbox — it is a system.

How the US Import Process Works: Step by Step

Understanding the sequence matters. Many compliance problems happen because importers act too late — or skip steps entirely.

Step 1: Obtain an Importer of Record (IOR) Number

Before your first shipment, you need an IOR number. For US companies, this is typically your federal Employer Identification Number (EIN). Individuals can use a Social Security Number or apply for a CBP-assigned number. Foreign entities importing without a US presence use a CBP-assigned number obtained through Form 5106.

The importer of record is legally responsible for all customs declarations, regardless of who physically files them.

Step 2: Classify Your Goods with an HTS Code

Every item imported into the US must be assigned a 10-digit Harmonized Tariff Schedule (HTS) code using the Harmonized Tariff Schedule of the United States. The first six digits align with the international Harmonized System; the final four are US-specific and determine the exact duty rate, any quota restrictions, and statistical reporting.

HTS classification follows the General Rules of Interpretation (GRIs). When the classification is ambiguous, you can request a free CBP Binding Ruling — a written CBP determination that is legally binding on both parties.

Step 3: File the Importer Security Filing (ISF) for Ocean Shipments

For ocean cargo, the ISF (commonly called “10+2”) must be transmitted electronically to CBP at least 24 hours before goods are loaded onto a vessel at a foreign port. Under 19 CFR Part 149, this filing includes 10 data elements from the importer (seller, buyer, manufacturer, ship-to party, HTS codes, country of origin, etc.) and 2 from the carrier.

Missing or late ISF filings carry penalties up to $10,000 per violation and can result in a “do not load” order or increased exam scrutiny.

Step 4: Arrange Transportation and Obtain a Bill of Lading or Airway Bill

Your freight forwarder or carrier issues a bill of lading (ocean) or airway bill (air) that serves as the contract of carriage and document of title. This document is required to file the formal customs entry and to take possession of the cargo.

Step 5: File the Formal Entry Declaration

Within 15 calendar days of a vessel’s arrival in a US port, the importer or their licensed customs broker must file:

• CBP Entry Summary (Form 7501) — the primary document declaring classification, value, country of origin, and duty calculation
• Commercial invoice — must show the price paid or payable, seller and buyer information, a complete description of the goods, and country of origin
• Packing list — itemizes contents, weights, and dimensions
• Bill of lading or airway bill — proof of shipment

Formal entries are filed electronically through CBP’s Automated Commercial Environment (ACE) portal.

Step 6: Pay Duties and Fees

Duties are typically paid at time of entry filing, or within 10 working days if the entry is in “entry/immediate delivery” status. CBP calculates duties based on the declared customs value multiplied by the HTS duty rate, plus:

• Merchandise Processing Fee (MPF): 0.3464% of value, minimum $31.67, maximum $614.35 per formal entry
• Harbor Maintenance Fee (HMF): 0.125% of value on ocean entries (paid by the importer)
• Any applicable Section 301, 201, or 232 tariffs, or anti-dumping/countervailing duties

Step 7: Respond to CBP Examinations (If Selected)

CBP uses risk-based targeting to select shipments for examination. Types include:

• Document review — CBP reviews paperwork without examining cargo
• Tailgate exam — CBP opens and inspects a container at the port
• Intensive exam (CET) — full unloading and inspection, which can take several days

Exam fees (for CET exams, typically $800–$2,500+) are paid by the importer.

Step 8: Liquidation

After the entry is filed and cargo is released, CBP reviews the entry and issues a final duty assessment called liquidation, which typically occurs within 314 days of entry. If CBP disagrees with the declared value or classification, it can reliquidate the entry and issue an additional duty bill. Importers can protest a liquidation decision within 180 days under 19 USC 1514.

The Regulatory Framework Behind US Import Requirements

US import law is primarily governed by the Tariff Act of 1930 (19 USC), with implementing regulations in Title 19 of the Code of Federal Regulations (19 CFR).

Key regulatory provisions every importer should know:

Beyond CBP, other agencies impose “Partner Government Agency” (PGA) requirements that must be satisfied before cargo is released:

• FDA — food, drugs, cosmetics, medical devices (requires prior notice for food; some goods need import alerts cleared)
• USDA APHIS — plants, plant products, meat, poultry, live animals
• EPA — motor vehicles, engines, pesticides, chemicals
• CPSC — consumer products, toys, children’s items (requires CPSA testing and certification)
• ATF — firearms, ammunition, alcohol
• FCC — electronics and radio-frequency devices

Each agency has its own documentation requirements. PGA holds are among the most common reasons for cargo delays at US ports.

Real-World Import Scenarios: What Requirements Look Like in Practice

Scenario 1: E-commerce Seller Importing Electronics from China

A small business imports 500 units of Bluetooth speakers from a Chinese manufacturer, FOB Shanghai, invoice value $15,000.

Requirements triggered:

• Formal entry required (value over $2,500)
• ISF required (ocean shipment) — must be filed before vessel loading
• HTS classification under Chapter 85 (electrical machinery)
• Section 301 tariffs (List 3) apply — additional 25% on top of the base duty rate
• FCC compliance certification required for radio-frequency devices
• CPSC import surveillance may apply

Estimated landed duty cost: $15,000 × (base duty ~0% + Section 301 25%) = $3,750 in Section 301 duties alone, plus MPF of $51.97.

This is why a licensed customs broker is not a luxury — it is a cost-control tool. Search all CBP-licensed customs brokers to find one familiar with electronics imports.

Scenario 2: Food Importer Bringing Mexican Avocados by Truck

A produce distributor imports fresh avocados from Mexico by road at Laredo, TX.

Requirements triggered:

• USDA APHIS phytosanitary certificate confirming the goods meet pest-free requirements
• FDA prior notice submission (all food for human consumption)
• Informal or formal entry depending on shipment value
• Harbor Maintenance Fee does not apply (land border crossing)
• Perishable goods may qualify for immediate release programs to prevent spoilage

Browse brokers by US port of entry to find brokers licensed at the specific land border crossing your shipment will use — port-specific knowledge matters for land crossings.

Scenario 3: Manufacturer Importing Pharmaceutical Ingredients

A drug manufacturer imports active pharmaceutical ingredients (APIs) from India.

Requirements triggered:

• FDA import entry screening — APIs are considered drugs under the FD&C Act
• FDA Drug Master File may be required
• Facility registration with FDA for foreign manufacturers
• Potential import alert holds if the Indian facility has prior violations

For this level of complexity, working with a broker who specializes in pharmaceutical imports is essential. A generalist broker may not know whether your API is subject to an active import alert.

Common Mistakes and Misconceptions

Mistake 1: Assuming the Supplier Handles Customs

Incoterms (FOB, CIF, DDP) define which party pays freight costs — not who files customs. Under US law, the importer of record is always responsible for the customs entry, regardless of what the purchase agreement says. A supplier selling “DDP” (Delivered Duty Paid) to the US must still comply with US customs law, but many foreign suppliers are not equipped to do this correctly.

Mistake 2: Using the Supplier’s HTS Code Without Verification

Suppliers often provide HTS codes as a convenience. Those codes may reflect the export classification in their home country, not the US import classification. A 6-digit chapter heading may be correct; the 4-digit US-specific suffix that determines the actual duty rate often is not. Always verify using hts.usitc.gov or a licensed broker.

Mistake 3: Undervaluing Goods to Reduce Duties

Customs value under 19 USC 1401a is based on the transaction value — the price actually paid or payable for the goods when sold for export to the United States. Assists (tooling, dies, engineering work paid by the buyer), royalties, and proceeds of resale must be added to the declared value. Declaring only the invoice price when assists exist is a compliance violation.

Mistake 4: Ignoring Trade Remedy Duties

Section 301 (China), Section 232 (steel, aluminum), and anti-dumping/countervailing duties (AD/CVD) are assessed in addition to the base HTS duty rate. AD/CVD rates can exceed 200% of the customs value on certain products. Check the AD/CVD Orders database before finalizing a sourcing decision. Many importers discover AD/CVD exposure only after their cargo arrives.

Mistake 5: Missing the ISF Deadline

The 24-hour ISF rule is firm. Many importers treat ISF as their freight forwarder’s problem. But if the ISF is late or inaccurate, the importer of record receives the penalty notice — not the forwarder. Confirm ISF submission with your forwarder or broker before cargo is loaded.

Tools and Resources for US Import Compliance