Section 321 Customs Clearance: The Complete Guide

Section 321 customs clearance is the legal mechanism that allows low-value shipments — those valued at $800 or less per person per day — to enter the United States duty-free without a formal customs entry, under 19 USC 1321. For e-commerce businesses, direct-to-consumer importers, and supply chain managers routing individual orders, understanding this exemption can mean the difference between a streamlined, cost-effective import operation and an unexpected duty bill.

What Is Section 321 De Minimis? Definition and Overview

De minimis exemption: A provision of U.S. customs law codified at 19 USC 1321 and implemented through 19 CFR Part 10.151–10.153, which allows merchandise with a fair retail value of $800 or less to enter the United States free of duties, taxes, and formal entry requirements, provided no single person receives more than one such shipment per day from the same seller or source.

The term “de minimis” is Latin for “about minimal things.” In trade law, it signals that the value of the shipment is too small to warrant full customs processing. Congress has raised this threshold three times — from $200 in 1993, to $200 again by rule, to $800 in February 2016 under the Trade Facilitation and Trade Enforcement Act (TFTEA). That $800 threshold remains in effect today.

The scale of Section 321 usage is significant. According to CBP data, de minimis shipments entering the United States exceeded 1 billion packages in fiscal year 2023, up from roughly 134 million in 2015. The rise of cross-border e-commerce — particularly direct-to-consumer shipping from China, Canada, and Mexico — has driven this growth.

Not every shipment under $800 qualifies automatically. Exclusions, filing requirements, and anti-abuse rules apply. This guide explains all of them.

How Section 321 Customs Clearance Works: Step-by-Step

Section 321 entries are “informal entries” — simpler and faster than formal entries, but they still require data submission to CBP. Here is the end-to-end process:

Step 1: Confirm the Shipment Value

The declared value must be the fair retail value of the merchandise in the country of origin — not the discounted wholesale price, not the shipping cost, and not the price after a promotional code. CBP defines fair retail value as the price a buyer would pay at retail in the origin country (19 CFR Part 152).

Step 2: Verify Eligibility (Exclusions Check)

Before filing, confirm the goods are not subject to:

• Antidumping or Countervailing Duty (AD/CVD) orders — these apply regardless of shipment value. Check the Antidumping/Countervailing Duty Orders database maintained by the Department of Commerce.
• FDA prior notice requirements — food, drug, device, and cosmetic products often require advance notice under the Bioterrorism Act even in small quantities.
• CPSC-regulated products — certain children’s products, apparel, and electronics require documentation that does not disappear at the $800 threshold.
• Certain textile and apparel categories — some are excluded from de minimis treatment under trade agreements.
• Alcohol and tobacco — always require formal entry regardless of value.

Step 3: File Through ACE or AMS

Carriers (airlines, ocean carriers, truckers, couriers) or licensed brokers submit shipment data electronically through CBP’s ACE Portal or the Automated Manifest System (AMS). The data elements required include:

• Consignee name and address
• Shipper name and address
• Country of origin
• Merchandise description
• Declared value
• Carrier and tracking information

For courier shipments (FedEx, UPS, DHL, USPS), the courier typically handles this filing. For e-commerce operations managing their own logistics, a licensed customs broker can file on their behalf.

Step 4: CBP Review and Release

CBP runs the manifest data through its Automated Targeting System (ATS), which scores each shipment for risk. Low-risk shipments are released — often within hours. Higher-risk shipments may be:

• Held for examination at the port of entry
• Reclassified as requiring a formal entry (Type 11 informal or Type 01 formal)
• Seized if evidence of fraud or prohibited goods is found

Step 5: Delivery to Consignee

Once released, the shipment proceeds through the carrier’s domestic network to the consignee. No further CBP action is typically required unless CBP issues a post-release examination or audit notice.

The Regulatory Framework: What the Law Actually Says

Section 321 authority derives from two primary sources:

19 USC 1321 — The statutory basis. It grants the Secretary of the Treasury (delegated to CBP) authority to provide by regulation for the admission of goods free of duty when the amount of duty payable is “so small as to be negligible.” Congress set the current $800 threshold in the Trade Facilitation and Trade Enforcement Act of 2015 (Public Law 114-125), effective February 24, 2016.

19 CFR Part 10.151–10.153 — The implementing regulations. These specify the one-per-person-per-day limit, the fair retail value standard, the excluded product categories, and the record-keeping obligations carriers must maintain.

Notice of Proposed Rulemaking (2024) — In January 2024, the Biden administration published a proposed rule to exclude goods subject to Section 301 tariffs (most goods from China) from de minimis eligibility. As of this writing, that rule had not been finalized, but importers should monitor CBP.gov for updates. The executive order signed in early 2025 further tightened de minimis access for shipments from China and Hong Kong, with implementation occurring in phases.

CBP Informed Compliance Publication — CBP publishes guidance on de minimis treatment through its “What Every Member of the Trade Community Should Know” series. These are non-binding but reflect CBP’s enforcement posture.

Section 321 in Practice: Real-World Scenarios

Understanding how Section 321 applies — and where it breaks down — is best illustrated through concrete examples.

Scenario 1: Direct-to-Consumer E-Commerce (Qualifies)

A US consumer orders a $65 phone case from a vendor in Shenzhen, China. The package ships directly to the consumer’s home address via an express courier. The courier files a de minimis entry through AMS. CBP clears the shipment without duty. The consumer pays no import tax. This is the intended use case — individual retail purchases imported directly.

Scenario 2: FBA Seller Replenishing Inventory (Does Not Qualify)

An Amazon FBA seller orders 500 units of a product from a Chinese manufacturer, valued at $3 per unit ($1,500 total), and asks the manufacturer to ship them in two boxes of 250 units each ($750 per box) to the same warehouse address on the same day. This is shipment splitting — a direct violation of the one-person-per-day rule. CBP’s pattern analysis in ACE would likely flag this. Both shipments could be reclassified as a single formal entry subject to full duties and the Merchandise Processing Fee (MPF).

Scenario 3: Sample Shipment (Qualifies with Caveats)

A buyer at a US retailer requests product samples valued at $400 from a supplier in Vietnam. The goods qualify for Section 321 treatment if they are not subject to AD/CVD orders, are not alcohol or tobacco, and no other Section 321 shipment from that supplier arrives for the same person that day. If the samples are footwear or textiles, additional verification is required.

Scenario 4: Pharmaceutical Supplements (Does Not Automatically Qualify)

A US wellness company imports a shipment of herbal supplements valued at $600. Even though the value is under $800, FDA requires prior notice for food and dietary supplement imports under 21 CFR Part 1, Subpart I. The shipment is not automatically excluded from de minimis treatment, but it requires advance FDA notification — failure to file prior notice can result in refusal of entry regardless of customs value.

Common Mistakes and Misconceptions

Mistake 1: Assuming “Under $800” Means Automatic Clearance

The $800 threshold is necessary but not sufficient. Excluded product categories, AD/CVD coverage, and per-person-per-day limits all apply independently of value.

Mistake 2: Shipment Splitting

As described above, dividing a single commercial order into multiple sub-$800 packages is a violation. CBP uses ACE data analytics to identify patterns across shipments by consignee, supplier, and routing. Penalties include reclassification, back-duties, and in fraud cases, seizure under 19 USC 1592.

Mistake 3: Using Wholesale Price as the Declared Value

CBP requires fair retail value — the price the goods would sell for at retail in the origin country. Using the manufacturer’s cost price or a discounted bulk price understates the value and constitutes misrepresentation. This is one of the more common audit findings CBP issues in post-entry reviews.

Mistake 4: Ignoring Country-of-Origin Impacts

Section 321 does not insulate importers from country-of-origin rules. Goods that meet the $800 threshold but originate from countries subject to heightened scrutiny (including Section 301 tariff lists for China) may face reclassification under new rulemaking.

Mistake 5: Assuming Section 321 Applies to All Ports Equally

CBP processing capacity and examination rates vary significantly by port. High-volume e-commerce ports like Los Angeles/Long Beach, JFK, and Louisville handle the majority of de minimis volume. At some smaller ports, informal entry processing is less automated and may take longer. Browse U.S. ports of entry on CustomsBrokerIndex to understand broker coverage at your primary port.

Section 321 vs. Other Entry Types: Comparison

The MPF (Merchandise Processing Fee) alone — currently 0.3464% of value, with a minimum of $32.71 and a maximum of $634.62 per entry (rates effective 2024) — makes Section 321 meaningfully cheaper for qualifying shipments. At 500 shipments per month averaging $600 each, the MPF savings alone can exceed $16,000 monthly.

Tools and Resources for Section 321 Compliance

CBP.gov (https://www.cbp.gov): The authoritative source for de minimis policy updates, proposed rulemakings, and ACE filing guidance. Monitor the Trade section for regulatory changes.

ACE Portal (https://ace.cbp.gov): CBP’s trade processing platform. Brokers and self-filers submit entries, manifests, and documentation here.

Harmonized Tariff Schedule (https://hts.usitc.gov): Even for de minimis shipments, knowing the HTS classification of your product helps determine whether AD/CVD orders apply and anticipates reclassification risk.

CBP Binding Rulings Database (https://rulings.cbp.gov): Search past rulings for your product category to understand how CBP has treated similar goods. A binding ruling on product classification provides legal certainty before you commit to an import strategy.

AD/CVD Orders Database (https://www.trade.gov/us-antidumping-and-countervailing-duties-home-page): Check whether your product and country of origin are covered by an order before assuming de minimis eligibility.

NCBFAA (https://www.ncbfaa.org): The National Customs Brokers & Forwarders Association of America publishes compliance resources and maintains a membership directory of licensed professionals.

CustomsBrokerIndex.com: If your import volume or product mix is growing to the point where de minimis compliance requires active management — or if you’re importing anything that might be excluded — working with a licensed customs broker is the right call. You can search all CBP-licensed customs brokers by location and specialty, or browse brokers by state to find qualified professionals near you. For goods requiring specialist knowledge — pharmaceuticals, food products, electronics — browse by specialty to find brokers with the right expertise.

For a broader view of how customs clearance integrates with warehousing and fulfillment operations, see our related guide on 3PL with customs clearance and warehousing explained.