USA import duty and customs guide (2026)
Understand US import duty, HTS classification, additional tariff layers, customs valuation, MPF and HMF when estimating landed cost.
US import duty looks simple - one HTSUS rate times the invoice value - until you meet Section 301 China tariffs, Section 232 steel surcharges, the Merchandise Processing Fee and the Harbor Maintenance Fee stacking on the same entry. This guide walks through the exact 2026 arithmetic that a US customs broker files on CBP Form 7501.
The base formula
Duty = Entered value x HTSUS ad-valorem rate
Entered value is the transaction value in USD (FOB origin unless otherwise agreed), converted at the CBP quarterly rate in effect on the export date. The HTSUS rate comes from the eight-digit line for the good; the ten-digit statistical suffix does not change duty.
Section 301 and 232 surcharges
Section 301 now has three layers. The China lists (List 1 to List 4A) carry 7.5% to 25%. The forced-labor action (91 FR 47318) adds 10% or 12.5% by country on most products of 60 economies from 24 July 2026, with Section 232 goods and Annex I/II products exempt. Brazilian goods carry 25% Section 301 from 22 July 2026. Section 232 (Proclamation 11021 of 2 April 2026, as amended by Proclamation 11032) charges duty on the full customs value in tiers: 50% for Annex I-A articles, 25% for Annex I-B derivatives, 15% for certain derivatives and partner origins, and 10% where the metal was melted and poured in the US, under HTS 9903.82.xx (CBP CSMS 68855869). Layers stack: a Chinese steel fitting can carry the HTSUS base, the 25% China list duty and 50% Section 232, while the forced-labor layer does not apply to Section 232 goods. The 2025 reciprocal tariffs imposed under IEEPA no longer apply: the Supreme Court held on 20 February 2026 (Learning Resources v. Trump) that IEEPA does not authorise tariffs, and CBP stopped collecting them from 24 February 2026. Check the current Chapter 99 headings for the country of origin.
MPF and HMF fees
The Merchandise Processing Fee is 0.3464% of entered value, floored at USD 34.58 and capped at USD 670.86 per entry (FY2027 values from 1 October 2026, CBP Dec. 26-14). Manual entries pay a USD 4.15 surcharge. The Harbor Maintenance Fee is 0.125% of entered value on any ocean shipment discharged at a US port, uncapped. Air and truck entries pay MPF only.
De minimis and Section 321
The Section 321 de minimis exemption used to let shipments at or below USD 800 per consignee per day enter free of duty and fees. Since 29 August 2025 that duty-free treatment is suspended for goods from all countries, so low-value commercial shipments now pay the applicable duties and need a formal or informal entry. Budget duty on every consignment, whatever its value, and check current CBP guidance for postal shipments.
Postal shipments that are subject to PGA requirements, owe Chapter 98/99 duties, or claim Chapter 98 or FTA treatment must be formally entered from 20 Jan 2027 (CBP, 91 FR 66638); until then filers may use formal entry or the Entry Type 13 test.
Graham Act (signed 18 Sep 2026) and EO 14436 (16 Oct 2026, 91 FR 66627): 500% additional duty on Russian goods and 100% on goods from certain buyers of Russian oil/gas and evasion facilitators were enacted, but are WAIVED under Sec. 4 of the order as of 21 Oct 2026 and are not collected. The waiver can be withdrawn. Federal Register
Worked example
USD 25,000 shipment of Chinese-origin steel pipe fittings (HTSUS 7307.99.5060 - 4.3% base, 25% Section 301 China list, 50% Section 232 on full value if listed in Annex I-A; confirm the annex, and no forced-labor layer because Section 232 goods are exempt), ocean freight to Los Angeles. Illustrative only, not a ruling; any temporary country-wide surcharge is excluded:
- HTSUS duty: 25,000 x 4.3% = USD 1,075
- Section 301: 25,000 x 25% = USD 6,250
- Section 232: 25,000 x 50% = USD 12,500
- MPF: 25,000 x 0.3464% = USD 86.60
- HMF: 25,000 x 0.125% = USD 31.25
- Total US charges: USD 19,942.85 (79.8% of entered value)
Frequently asked questions
How is US import duty calculated?#
Duty = entered value x HTSUS ad-valorem rate. Entered value is the transaction value in USD (FOB origin, unless the parties agreed otherwise), converted at the CBP rate on the date of export. On top, you add the Merchandise Processing Fee (0.3464% of entered value, minimum USD 34.58 and maximum USD 670.86 in FY2027, from 1 October 2026) and, for ocean shipments, the Harbor Maintenance Fee (0.125% of entered value, no cap).
When do Section 301 and Section 232 tariffs apply?#
Section 301 now has three layers: the China lists (7.5% to 25%), the forced-labor action of 10% or 12.5% by country on most products of 60 economies (99.4% of US imports) from 24 July 2026, with Section 232 goods and Annex I/II products exempt, and 25% on Brazilian goods from 22 July 2026. Section 232 (Proclamation 11021 as amended by 11032) charges 50% / 25% / 15% / 10% tiers on the full customs value of steel, aluminium and copper articles and derivatives, by HTS heading 9903.82.xx. Layers stack where they apply, so confirm the current Chapter 99 headings before filing.
Is there still a USD 800 de minimis exemption in 2026?#
No, not for commercial shipments. From 29 August 2025 the United States suspended duty-free de minimis treatment under Section 321 for goods from all countries, so low-value commercial parcels now pay the applicable duties and need an entry. The USD 800 statutory figure still exists in the law, but the suspension means you should not promise duty-free entry for low-value shipments. Check current CBP guidance for the entry type and any postal-shipment rules.
How do I use HTSUS chapter and heading numbers?#
HTSUS is a ten-digit code: the first six digits align with the WCO Harmonized System (used worldwide), digits 7-8 are US-specific tariff distinctions, and digits 9-10 are statistical suffixes for trade data. The duty rate lives at the eight-digit level; brokers file at ten digits. The HS Code Lookup tool cross-walks a description to the eight-digit US line.
Which incoterm minimises US import duty?#
None - duty is a function of goods value and classification, not incoterm. What incoterm affects is who declares the value and pays. Under DDP the seller becomes the Importer of Record and pays; under FOB / CIF the buyer is IOR. FCA is popular for US inbound because it lets the buyer control the freight (and use their forwarder) while the seller still hands over at origin.