Importing is the process of bringing foreign-produced goods into the United States for sale, use, or distribution — and it is governed by one of the most detailed regulatory frameworks in global trade. Understanding how the import process works is essential for any business sourcing goods from abroad, because errors in classification, valuation, or documentation can result in shipment delays, financial penalties, or seizure of merchandise.
What Importing Means Under US Law
Importing (US legal definition): The introduction of foreign merchandise into the commerce of the United States, as defined under 19 USC 1401, which requires that all commercial shipments pass through a designated port of entry and be declared to U.S. Customs and Border Protection (CBP) before the goods are released for domestic use.
This definition has a few important implications. First, not every cross-border movement qualifies as a formal import entry — small-value shipments under $800 (the “de minimis” threshold established by 19 USC 1321) typically enter without a formal entry filing and without paying duties. Second, every commercial import above that threshold requires a formal entry, a responsible party called the importer of record, and payment of applicable duties and fees.
The United States imported approximately $3.1 trillion in goods in 2023, according to the U.S. Census Bureau. The top import categories by value were industrial supplies and materials, capital goods (excluding vehicles), consumer goods, automotive vehicles and parts, and food and beverages. China, Mexico, and Canada are consistently the three largest source countries for US imports.
The agency responsible for administering import laws is U.S. Customs and Border Protection, which operates under the Department of Homeland Security and processes more than 36 million cargo entries per year.
How the US Import Process Works
Importing a commercial shipment into the United States follows a defined sequence. Missing or mishandling any step can delay cargo release — sometimes by days, sometimes by weeks.
Step 1: Purchase and Shipment Preparation
The importer contracts with a foreign supplier, negotiates Incoterms (e.g., FOB, CIF, DDP), and arranges transportation. The supplier prepares a commercial invoice, packing list, and — for ocean shipments — a bill of lading. These documents form the foundation of the customs entry.
Step 2: Importer Security Filing (ISF)
For ocean freight shipments, the importer or their customs broker must file an Importer Security Filing (ISF-10) with CBP at least 24 hours before the vessel is loaded at the foreign port. This requirement, established under 19 CFR Part 149, applies to all ocean shipments destined for the US. Failure to file on time carries penalties of up to $10,000 per violation.
Step 3: Arrival at Port of Entry
When the vessel, aircraft, or truck arrives at a US port of entry, CBP receives a manifest from the carrier. The cargo is placed in a bonded area (warehouse or terminal) where it remains under CBP custody until the entry is filed and approved.
Step 4: Entry Filing
The importer of record — or a licensed customs broker acting on their behalf — files a customs entry through CBP’s Automated Commercial Environment (ACE) portal. The entry includes:
- Entry summary (CBP Form 7501)
- Commercial invoice
- Packing list
- Bill of lading or airway bill
- HTS classification for each product line
- Declared customs value
CBP uses this information to calculate applicable duties, taxes, and fees.
Step 5: CBP Review and Examination
CBP uses automated risk-scoring systems to determine whether a shipment will be released immediately (green lane), flagged for document review (yellow lane), or held for physical examination (red lane). Approximately 4% of commercial entries are physically examined, according to CBP operational data. Examinations can add 2–10 business days to clearance timelines.
Step 6: Duty Payment and Release
Once CBP approves the entry, duties and fees are assessed. The importer pays these amounts — typically through a broker’s bond account — and CBP releases the cargo. The importer can then arrange inland delivery.
Step 7: Post-Entry Compliance
CBP retains the right to audit import records for up to five years after entry under 19 CFR Part 163. Importers must keep all entry-related records for this period. CBP can issue penalty notices, demand additional duties, or initiate seizure proceedings based on post-entry reviews.
The Regulatory Framework for US Imports
US import law is primarily governed by the Tariff Act of 1930 (codified at Title 19 of the US Code) and its associated regulations in Title 19 of the Code of Federal Regulations (19 CFR). The key legal provisions every importer should know:
- 19 USC 1484 — establishes the right and obligation of the importer of record to make entry and pay applicable duties
- 19 USC 1401a — defines the five methods of customs valuation (transaction value, identical merchandise value, similar merchandise value, deductive value, computed value)
- 19 CFR Part 152 — the implementing regulations for customs valuation
- 19 CFR Part 141 — entry requirements, including who can file and what documents are required
- 19 CFR Part 149 — ISF requirements for ocean shipments
- 19 CFR Part 163 — recordkeeping obligations for importers and brokers
Beyond CBP, more than 40 partner government agencies (PGAs) regulate specific product categories. The FDA regulates food, drugs, medical devices, and cosmetics. The USDA Animal and Plant Health Inspection Service (APHIS) regulates agricultural products. The EPA regulates vehicles, engines, and certain chemicals. Importers of regulated goods must satisfy both CBP and the relevant PGA before cargo is released.
For antidumping and countervailing duty (AD/CVD) orders — which apply additional duties to specific goods from specific countries when foreign producers are found to be selling below market price — the current list is maintained at the Antidumping/Countervailing Duty Orders database.
Types of Import Entries and Their Requirements
Not all imports are processed the same way. CBP recognizes several formal entry types, each with different requirements and use cases.
| Entry Type | When It Applies | Bond Required | Duty Payment |
|---|---|---|---|
| Informal Entry (Type 11) | Goods valued $800–$2,500, non-commercial | No | At time of entry |
| Formal Consumption Entry (Type 01) | Commercial goods over $2,500 | Yes | Within 10 days of entry summary |
| Immediate Delivery (Type 03) | Perishables, express, air cargo | Yes | Within 10 days |
| Warehouse Entry (Type 21) | Goods stored in a bonded warehouse | Yes | Deferred until withdrawal |
| Temporary Importation Under Bond (Type 23) | Goods returning abroad (samples, equipment) | Yes | Waived if re-exported |
| Section 321 De Minimis (Type 86) | E-commerce shipments under $800 | No | None |
The Merchandise Processing Fee (MPF) applies to most formal entries: 0.3464% of cargo value, with a minimum of $32.71 and a maximum of $614.35 as of 2024. Ocean freight shipments also incur a Harbor Maintenance Fee (HMF) of 0.125% of cargo value.
Real-World Importing Scenarios
Understanding the process in the abstract is one thing — seeing how it plays out in practice is more useful.
Scenario 1: E-commerce seller importing electronics from China
A US-based Amazon seller orders 500 units of Bluetooth speakers from a Shenzhen manufacturer. The commercial invoice value is $15,000. The seller’s customs broker classifies the goods under HTS 8518.22 (loudspeakers, multiple, mounted in an enclosure), which carries a base duty rate of 0% — but Section 301 tariffs on Chinese-origin electronics add a 7.5% additional duty. The total duty bill is $1,125 plus MPF of $52. The broker files an ISF 48 hours before loading and a formal consumption entry upon arrival at the Port of Los Angeles. Clearance takes 36 hours with no examination.
Scenario 2: Food importer bringing produce from Mexico
A Texas distributor imports 10,000 kg of fresh avocados weekly via the Laredo land border crossing. The goods require both CBP clearance and USDA APHIS inspection. The broker files entries under HTS 0804.40 (avocados, fresh), which carries a 0% duty rate under the USMCA agreement. The USDA inspection adds 4–6 hours to the clearance timeline. The importer uses a continuous import bond to cover ongoing weekly shipments rather than filing a single-entry bond each time.
Scenario 3: Manufacturer importing industrial machinery
A Michigan auto parts manufacturer imports a CNC milling machine from Germany valued at $280,000. The HTS classification is 8457.10, carrying a 4.4% duty rate — a $12,320 duty bill. The machine qualifies for a temporary importation under bond (TIB) entry instead, since it will be used to produce goods for re-export, deferring the duty obligation entirely. The importer must re-export the machine or pay the duties plus a penalty within the TIB period (typically one year, extendable).
You can find brokers who specialize in these scenarios — from electronics and consumer goods to food, automotive, and industrial equipment — by browsing by specialty on CustomsBrokerIndex.
Common Importing Mistakes and How to Avoid Them
Most import compliance failures trace back to a small set of recurring errors. Knowing them in advance is far cheaper than learning through a CBP penalty notice.
Misclassifying HTS codes. Every product imported into the US must be assigned a 10-digit Harmonized Tariff Schedule code. The duty rate, any applicable trade remedy tariffs, and partner government agency requirements all flow from this classification. Using the wrong code — even by one digit — can mean underpaying duties (triggering back-payment demands and penalties under 19 USC 1592) or overpaying unnecessarily. Use the Harmonized Tariff Schedule lookup at hts.usitc.gov or request a binding ruling from CBP at rulings.cbp.gov to lock in a classification before large-volume shipments.
Undervaluing merchandise. Customs value is not simply the price paid on the invoice. Under 19 USC 1401a, transaction value — the price actually paid or payable for goods when sold for export to the US — is the preferred valuation method, and it must include assists (tooling, molds, or engineering provided free to the supplier), royalties, and any additional payments. CBP regularly audits importers in industries where undervaluation is common, including textiles, footwear, and electronics.
Missing the ISF deadline. The 24-hours-before-loading rule for ocean shipments is hard. Many first-time importers don’t know it applies, or they provide incomplete information. Penalties start at $5,000 per late filing and go up to $10,000 per violation for inaccurate filings, per CBP guidelines.
Overlooking trade agreements. If your goods qualify for preferential duty treatment under a US free trade agreement — USMCA, the Korea FTA, the US-Japan Trade Agreement — you must claim the preference on the entry by providing a valid certificate or certification of origin. Many importers pay full duty rates when they don’t have to simply because no one asked whether the goods qualify.
Not working with a licensed broker. While US law permits self-filing, the combination of HTS classification, valuation rules, ISF timing, and PGA requirements creates significant compliance complexity. A licensed customs broker — you can search all CBP-licensed customs brokers at CustomsBrokerIndex — is accountable to CBP for the accuracy of entries they file, which creates a professional incentive structure that protects the importer.
To understand the full scope of what a customs broker does on your behalf, see 10 Core Duties of a Customs Broker Explained and 10 Key Customs Broker Responsibilities Explained.
Tools and Resources for Importers
The following tools are publicly available and genuinely useful — not paywalled industry databases.
CBP’s Automated Commercial Environment (ACE): The primary portal for filing customs entries, checking shipment status, and managing importer accounts. Accessible at cbp.gov.
HTS Online (hts.usitc.gov): The official searchable version of the Harmonized Tariff Schedule. Use the search function and browse the chapter notes — the notes often determine classification disputes.
CBP Binding Rulings (rulings.cbp.gov): A searchable database of classification and valuation decisions CBP has issued to importers. If someone has imported a similar product, there’s likely a ruling on record. Binding rulings can be requested directly from CBP and, once issued, are legally binding on CBP for the described goods.
AD/CVD Order Database (enforcement.trade.gov/adcvd): If you’re importing from China, Vietnam, India, or other countries with active trade disputes, check this database before finalizing your sourcing decision. AD/CVD rates can reach 200%+ on affected goods.
International Trade Administration (trade.gov): Offers market intelligence, country-specific trade data, and resources