I. U.S. Customs and Border Protection (CBP)
U.S. customs is administered by the U.S. Customs and Border Protection (CBP) , an agency under the Department of Homeland Security (DHS).
Key Points:
- U.S. import clearance must be handled by a Customs Broker licensed in the United States
- Non-U.S. companies or individuals cannot file directly with CBP
- CBP applies the "Reasonable Care" principle — importers are responsible for the accuracy of their declarations
II. Main Documents for U.S. Import Clearance
| Document | Description |
| Commercial Invoice | Product description, HS code (HTSUS), quantity, value, country of origin |
| Packing List | Packaging details, weight, volume |
| Bill of Lading (B/L) | Ocean bill of lading or air waybill |
| ISF Filing (Importer Security Filing) | Must be submitted 24 hours before vessel loading |
| AMS Filing (Automated Manifest System) | Sent by carrier or NVOCC (bill-of-lading level information) |
| Importer Security Filing (10+2) | ISF = 10 importer data items + 2 carrier data items |
| CBP Form 3461 (Entry Manifest) | Basic entry information |
| CBP Form 7501 (Entry Summary) | Complete customs declaration (similar to China's customs declaration form) |
III. ISF/AMS Filings
3.1 ISF (Importer Security Filing)
ISF (Importer Security Filing) , commonly known as the "10+2" filing.
| Item | Requirement |
| Filing deadline | 24 hours before the cargo is loaded onto the vessel overseas |
| Filer | Importer or their authorized customs broker/freight forwarder |
| 10 data items | Seller, buyer, importer of record number, consignee, manufacturer, ship-to party, port of destination, vessel/voyage, container stuffing location, goods information |
| 2 carrier data items | Vessel name and voyage number provided by carrier, container stowage plan |
Consequences of late or non-filing:
- Penalties (starting at $5,000)
- Goods subject to mandatory inspection at destination port
- In severe cases, goods may be denied entry
3.2 AMS (Automated Manifest System)
AMS (Automated Manifest System) is the manifest data sent to CBP by the carrier/NVOCC, completed before vessel loading.
AMS data is sent by the carrier; importers or forwarders must ensure the accuracy of AMS information.
IV. U.S. Tariff Inquiry
4.1 HTSUS Code
The U.S. uses the HTSUS (Harmonized Tariff Schedule of the United States) coding system. The first 6 digits of the U.S. HS code are identical to China's, with the last 4 digits being U.S.-specific subdivisions (10-digit total).
How to look up:
- U.S. International Trade Commission (USITC) website: hts.usitc.gov
- CBP website: www.cbp.gov/trade
4.2 Tariff Types
| Tariff Type | Description |
| MFN/NTR Rate (Most-Favored-Nation / Normal Trade Relations) | Applies to China and other WTO members (baseline rate) |
| Section 301 Additional Tariffs | Extra tariffs on specific Chinese goods (in effect since 2018) |
| General Rate | Applies to non-WTO members |
| Preferential Rate | Applies to countries with FTA with the U.S. (not applicable to China) |
4.3 Section 301 Tariffs
Since 2018, the U.S. has imposed additional tariffs on Chinese goods under the "Section 301" investigation findings. As of 2026:
- Product scope: approximately $200 billion worth of Chinese goods
- Additional tariff rates: 7.5%–25% (depending on product category)
- Exclusion mechanism: some products may qualify for temporary exclusions through application
Impact on exporters: Exports to the U.S. must factor in both MFN rates and Section 301 additional tariffs, significantly increasing total tariff costs.
V. Major U.S. Regulatory Agencies
| Agency | Scope | Common Requirements |
| FDA (Food and Drug Administration) | Food, drugs, cosmetics, medical devices | Product registration + import alerts + port inspection |
| CPSC (Consumer Product Safety Commission) | Consumer goods (toys, electronics, apparel, etc.) | Product safety standards + test reports |
| USDA/APHIS (Animal and Plant Health Inspection Service) | Agricultural products, wood, animal/plant products | Phytosanitary permits + treatment certificates |
| EPA (Environmental Protection Agency) | Chemicals, pesticides | Registration + TSCA compliance |
| TTB (Alcohol and Tobacco Tax and Trade Bureau) | Alcoholic beverages, tobacco products | Import permits + label approval |
FDA Inspection
FDA enforces strict port-of-entry inspection for imported food, drugs, and cosmetics:
| FDA Inspection Type | Description |
| May Release | Low-risk goods released directly |
| Document Review | Documentation required for review (3–7 days) |
| Physical Examination | Sampling and testing (1–4 weeks) |
| Detention | Non-compliant goods detained; if not passed, must be returned or destroyed |
VI. Practical Customs Clearance After Arrival in the United States
After the goods arrive at a U.S. port, customs clearance consists of two steps: Entry and Entry Summary, all submitted electronically through CBP's ACE system (Automated Commercial Environment). ACE is also the unified entry point for Partner Government Agency (PGA) filings—import data for agencies such as FDA, CPSC, USDA, and EPA is all filed there together; therefore, what the customs broker submits is one set of data, not multiple sets of forms.
6.1 Pre-arrival Preparation Checklist
| Item | Confirmation |
|---|---|
| ISF filing | Filed 24 hours before vessel loading, with no discrepancies flagged by CBP |
| Entry (CBP Form 3461) | Submitted in ACE by a licensed customs broker; can be processed once the goods arrive |
| PGA filing | Confirm based on the product's classification whether FDA / CPSC / USDA / EPA filing is required |
| Bond | Confirm that the customs broker's bond amount covers the value and duties/fees of this shipment |
| Transaction documents | Contract, invoice, payment receipt, and freight documents are ready for valuation verification |
6.2 Four Stages After Arrival
| Stage | Action | Time Reference |
|---|---|---|
| ① Review and Release Decision | CBP conducts risk analysis of the customs data through ACE; if not selected, electronic release is granted | Usually within 1 business day after arrival |
| ② Inspection (if selected) | Conducted by CBP or a Centralized Examination Station (CES); see 6.3 for types | Depending on scheduling, from several days to more than two weeks |
| ③ Payment of Duties and Fees | Customs duties, Merchandise Processing Fee (MPF), Harbor Maintenance Fee (HMF) | Before release |
| ④ Entry Summary and Cargo Pickup | Submit CBP Form 7501 (Entry Summary), then arrange cargo pickup and container return | Within 10 business days after release |
Note: The 10 business days for the Entry Summary is a statutory deadline; overdue submission may result in interest and penalties; in practice, most customs brokers submit it on the same day or the next day after release, without waiting for the deadline to expire.
6.3 Three Types of CBP Inspections
| Type | English / Abbreviation | Description |
|---|---|---|
| Non-Intrusive Inspection | NII / X-ray | Container passes through X-ray or gamma ray; no unpacking; shortest time required |
| Tailgate Inspection | Tailgate | Open the container doors for visual verification; partial unpacking as needed |
| Intensive Exam | Intensive Exam | Full unpacking and piece-by-piece verification; longest time and highest cost |
Inspections are conducted by CBP or authorized Centralized Examination Stations (CES), and incur inspection service fees, drayage fees, and storage fees; port storage time continues to accrue during the inspection. Whether an inspection is selected is determined by CBP's risk parameters; declaration quality and the importer's history both affect the probability of selection.
6.4 Free Time, Demurrage, and Detention
- Free Time: The number of free days the carrier grants for container use; common for ocean imports is 3–7 days; the specific terms are subject to the bill of lading or freight rate terms
- Demurrage: Fees incurred when a container stays at the terminal yard beyond the free time; generally calculated from the date of vessel discharge
- Detention: Fees incurred when a container is not returned after leaving the terminal beyond the free time
- Customs clearance delays are the main cause of demurrage—late ISF filing, failure to file PGA, and valuation disputes all directly increase this cost
6.5 Composition of Duties and Fees
Duties and fees at the U.S. import stage consist of three parts: customs duties (calculated according to HTSUS rates, including Section 301 additional tariffs if applicable), Merchandise Processing Fee (MPF), and Harbor Maintenance Fee (HMF). MPF and HMF are calculated according to the rates and upper/lower limits set by CBP; the specific standards are subject to CBP official announcements.
VII. Clearance Recommendations for Exports to the U.S.
| Recommendation | Description |
| Secure a U.S. customs broker | Find a licensed U.S. customs broker before exporting |
| Don't miss ISF filing | ISF deadline is 24 hours before vessel loading — easy to overlook |
| Monitor Section 301 tariff updates | Additional tariff scope and rates are frequently adjusted |
| Product compliance in advance | Verify FDA/CPSC and other compliance requirements before shipping |
| Customs valuation | U.S. customs strictly reviews transaction value and related-party transactions |
VIII. Common Reasons for Customs Clearance Failure and How to Respond
| Cause | Manifestation After Arrival | Response |
|---|---|---|
| Late or Missing ISF Filing | Flagged as noncompliant; cargo subject to mandatory inspection; possible fines | Confirm filing 24 hours before vessel loading and verify the receipt |
| Incorrect HTSUS Classification | Even after release, it may still be retroactively adjusted, requiring duty payment and possibly fines | Confirm the 10-digit code with the customs broker before export, and apply for a CBP advance ruling if necessary |
| Declared Value Questioned | Release is suspended; additional transaction documents are required | Keep the contract, invoice, payment receipt, and freight documents ready |
| Missing PGA Declaration | FDA / CPSC and other agencies detain the goods; additional filing or return shipment is required | Before export, confirm whether the product falls under PGA jurisdiction and complete registration/filing |
| Wood Packaging Without ISPM-15 Mark | Required to be returned or destroyed | Use treated wooden pallets bearing the IPPC mark |
| Anti-dumping / Countervailing Duty (AD/CVD) Not Declared | Cash deposits are pursued; cargo is detained | Verify whether the goods fall within the scope of AD/CVD orders and confirm the declaration basis in advance |
| Incomplete Importer Qualifications | Customs declaration cannot be submitted | Confirm that the U.S. importer has an EIN and has completed relevant CBP filings |
The above is a summary of common situations; specific determinations and handling are subject to the latest regulations of CBP and the competent authorities.
Note: This article is provided for general knowledge only. Bofeng Logistics does not provide destination customs clearance agency, consulting or assistance services in the United States. We provide China-side export declaration and international ocean freight booking; clearance at the destination must be handled by the importer or its local customs broker.
For a complete U.S. ocean import document checklist, see U.S. Ocean Import Documents: ISF Filing, AMS & Customs Clearance.
📖 Next: 6.2 EU Import Clearance Guide — EORI, Import VAT, REACH, CE Certification
Bofeng Logistics specializes in domestic/international container shipping, Hong Kong/Macau dedicated logistics services, and value-added services (trucking, customs declaration, warehousing, insurance).
Customs declaration service areas: Zhuhai, Guangzhou, Shenzhen.
Further Reading
- Complete Import Customs Clearance Process: A step-by-step guide to bill of lading exchange upon arrival, customs declaration and tax payment, inspection and release, and cargo pickup
- Complete Checklist of Documents for U.S. Ocean Freight Imports: ISF filing, AMS manifest, and coordinated customs clearance process
- EU Import Customs Clearance Guide: EORI number, import VAT, CE certification, and REACH regulations
- Japan Import Customs Clearance Guide: NACCS system, RCEP tariff concessions, and JCT consumption tax
- Import Customs Clearance Guide for Five Countries: Mexico, Russia, Canada, Australia, and South Korea: NOM/EAC/ACI, biological quarantine, and KC certification
- International Ocean Freight Import Services: End-to-end import support from overseas shipment to domestic pickup
- Guide to Responding to Customs Inspections: Inspection Methods, Factors Affecting Inspection Rates, and Practical Responses
- China-U.S. International Ocean Freight Route: Major Ports, Sailing Schedules, and Arrival Coordination
Frequently Asked Questions
Who is responsible for filing ISF 10+2?
The legal responsibility lies with the U.S. importer, and it is usually filed by its authorized U.S. customs broker or freight forwarder 24 hours before the cargo is loaded onto the vessel. Late or missed filings may result in CBP fines of up to $5,000 per violation; specific penalties are subject to CBP official regulations.
What multiple layers of tariffs must be checked for goods exported from China to the United States?
First check the most-favored-nation rate using the HTSUS code, then verify whether the goods are included in the Section 301 list and the applicable additional tariff rate; if the goods are exempt, apply the rate in effect during the exemption period. The final applicable tariff rate is subject to the official U.S. tariff schedule and CBP rulings.
How long after the cargo arrives at the port can it be released?
When documents are complete and the shipment has not been selected for inspection, electronic release usually occurs within 1–3 business days after arrival at the port; if it is selected for inspection, inspection scheduling and processing time must be added, which may extend it by several days to more than two weeks. Actual timing is subject to CBP and port operating arrangements.
From which day is the free container period calculated?
It generally starts from the date the container is discharged from the vessel. The number of days is stipulated by the carrier in the bill of lading or tariff terms; exceeding the period incurs container detention fees. It is recommended to confirm the number of free container days and container return requirements with the freight forwarder at the booking stage.
This article was prepared by the Bofeng Logistics team and reviewed in September 2026. Customs rules change frequently; refer to official customs and authority notices for the latest requirements.
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