Trade glossary

HS code

The Harmonized System code — a six-digit product code used by most countries to classify traded goods.

HTS code

The Harmonized Tariff Schedule code — the ten-digit US extension of the HS code. The first six digits are the international HS code; the remaining digits are US-specific.

Entered value

The customs value a duty is calculated on — generally the price paid for the goods, excluding international freight and insurance.

MFN rate

The most-favored-nation rate, also called the normal-trade-relations (NTR) rate — the ordinary duty that applies to imports from most trading partners.

Ad valorem rate

A duty expressed as a percentage of the entered value.

Specific rate

A duty expressed as a fixed amount per unit of quantity, such as per kilogram.

Compound rate

A duty combining an ad valorem percentage and a specific per-unit amount.

Section 301

Additional US tariffs on many goods from China, imposed in response to a trade-practices investigation. See the Section 301 explainer.

Section 232

National-security tariffs on steel, aluminum, copper, their derivatives, and autos. See the Section 232 explainer.

Section 122

A temporary 10% emergency tariff that expired July 24, 2026 by its statutory terms. See the Section 122 explainer.

IEEPA

The International Emergency Economic Powers Act. Tariffs imposed under IEEPA were ruled unauthorized by the Supreme Court; duties paid may be refundable through CAPE.

CAPE

Consolidated Administration and Processing of Entries — CBP's process for refunding IEEPA duties. See the CAPE refunds explainer.

MPF

The Merchandise Processing Fee — a small US customs fee charged as a percentage of entered value, with a minimum and maximum per entry.

HMF

The Harbor Maintenance Fee — a US customs fee on ocean shipments, charged as a percentage of entered value.

AD/CVD

Antidumping and countervailing duties — additional duties on specific goods sold below fair value or benefiting from foreign subsidies. Portigo flags their presence but does not compute their rates.

FTA

A free trade agreement, such as USMCA. Goods that qualify under an FTA's rules of origin may receive a preferential (reduced or zero) duty rate.

Chapter 99

The section of the US tariff schedule that carries temporary tariff measures, including the Section 301 and 232 surcharges (and Section 122 until it expired in July 2026).

Column 2 rate

The higher duty rate applied to goods from a small number of countries that do not have normal trade relations with the United States.

TRQ

A tariff-rate quota — a lower duty rate up to a set import quantity, and a higher rate beyond it.

Section 201

A safeguard tariff used to give a domestic industry temporary relief from a surge in imports.

Country of origin

The country where goods were produced or substantially transformed — it determines which tariffs and preferences apply.

These definitions are plain-English summaries, not legal definitions. Portigo does not give legal or compliance advice. Confirm specifics against the USITC HTS database or a licensed customs broker.