Tandom · Duty calculator
HTS 7307.91.10.00 is the U.S. Harmonized Tariff Schedule classification for Of iron or nonalloy steel. It's a 10-digit statistical line in Chapter 73: Articles of iron or steel, Section XV: Base Metals and Articles of Base Metal, used by U.S. Customs and Border Protection to determine the duty rate at entry. 9 Chapter 99 tariff modifications currently stack on top of the base rate, and 2 active AD/CVD orders flag this code.
New to HTS codes? Read our guide on how HTS classification works →
Chapter 99 overlays that stack on the base rate
| Code | Authority | Rate |
|---|---|---|
| 9903.80.03 | section_232 | The duty provided in the applicable subheading + 25% |
| 9903.81.84 | section_232 | The duty provided in the applicable subheading + 25% |
| 9903.81.86 | section_232 | The duty provided in the applicable subheading + 25% |
| 9903.81.90 | section_232 | The duty provided in the applicable subheading + 50%. |
| 9903.81.92 | section_232 | The duty provided in the applicable subheading. |
| 9903.81.93 | section_232 | The duty provided in the applicable subheading + 50%. |
| 9903.81.97 | section_232 | The duty provided in the applicable subheading + 25% |
| 9903.81.99 | section_232 | The duty provided in the applicable subheading + 25% |
| 9903.82.02 | section_232 | 50% |
Active orders that may apply to imports under this HTS code. HTS coverage is advisory — actual scope depends on each order's product description. Run the AD/CVD lookup → to check whether your specific shipment is in scope.
HTS 7307.91.10.00 is the U.S. Harmonized Tariff Schedule classification for Of iron or nonalloy steel. It belongs to Chapter 73 of the HTSUS.
The general (Column 1) duty rate for HTS 7307.91.10.00 is 3.3%. This is the most-favored-nation (MFN) rate that applies to imports from World Trade Organization member countries.
Yes. Imports of HTS 7307.91.10.00 from countries party to a trade program (such as USMCA, KORUS, GSP, or the African Growth and Opportunity Act) may qualify for the special rate: Free (A,AU,BH,CL,CO,D,E,IL,JO,JP,KR,MA,OM,P,PA,PE,S,SG). Eligibility depends on rules of origin and certification.
The Column 2 rate for HTS 7307.91.10.00 is 25%. This rate applies to imports from countries that do not have normal trade relations with the United States (currently Cuba and North Korea).
Yes — HTS 7307.91.10.00 is covered by section_232 provision 9903.80.03 (The duty provided in the applicable subheading + 25%). 8 additional overlays also touch this code. Open the code page for the full overlay stack with effective dates and country scopes.
Yes — 2 AD/CVD orders flag this code: A-588-831 (AD, Japan), A-588-702 (AD, Japan). Open the code page for deposit rates, scope determinations, and the linked case lookups.
Free Trade Agreement and special-program eligibility
Section and chapter notes that govern this code
This section does not cover: (a) Prepared paints, inks, or other products with a basis of metallic flakes or powder (headings 3207 to 3210, 3212, 3213, or 3215); (b) Ferro-cerium and other pyrophoric alloys (heading 3606); (c) Headgear and parts thereof of heading 6506 or 6507; (d) Umbrella frames or other articles of heading 6603; (e) Goods of chapter 71 (for example, precious-metal alloys, base metal clad with precious metal, imitation jewelry); (f) Articles of section XVI (machinery, mechanical appliances, and electrical equipment); (g) Assembled railway or tramway track (heading 8608); (h) Articles of section XVII (vehicles, aircraft, vessels); (ij) Instruments or apparatus of section XVIII (clocks, optical, musical, arms); (k) Lead shot prepared for ammunition (heading 9306); (l) Articles of section XX (furniture, toys, games, sports); or (m) Hand sieves, buttons, pens, pencil holders, pen nibs, monopods, bipods, tripods, and similar articles of section XX.
Throughout this schedule, the expression 'parts of general use' means: (a) Articles of heading 7307, 7312, 7315, 7317, or 7318, and similar articles of other base metal; (b) Springs and leaves for springs, of base metal, other than clock or watch springs (heading 9114); and (c) Articles of headings 8301, 8302, 8308, 8310.
Throughout this schedule, the expression 'base metals' means: iron and steel, copper, nickel, aluminum, lead, zinc, tin, tungsten (wolfram), molybdenum, tantalum, magnesium, cobalt, bismuth, cadmium, titanium, zirconium, antimony, manganese, beryllium, chromium, germanium, vanadium, gallium, hafnium, indium, niobium (columbium), rhenium, and thallium.
Classification of alloys: (a) Alloys of base metals with each other are to be classified as alloys of the metal which predominates by weight over each of the other metals; (b) Alloys of base metals of this section with elements not falling within this section are to be classified as alloys of base metals of this section if the total weight of such metals equals or exceeds the total weight of the other elements present; (c) Sintered mixtures of metal powders, heterogeneous intimate mixtures obtained by melting (other than cermets), and intermetallic compounds are classified as alloys.
(a) 'Iron and nonalloy steel' covers iron and steel containing by weight 2% or less of carbon and, except for certain specific steels, less than designated percentages of chromium, manganese, nickel, and other alloy elements. (b) 'Stainless steel' covers alloy steels containing by weight 1.2% or less of carbon and 10.5% or more of chromium, with or without other elements. (c) 'Other alloy steel' covers steels not meeting the definition of stainless steel containing specific minimum percentages of alloy elements.
In this chapter, the expression 'cast iron' applies to products obtained by casting in which iron predominates by weight over each of the other elements and which do not comply with the chemical composition of steel as defined in note 1(d) to chapter 72.
Heading 7307 covers fittings used in piping systems for connecting, adapting, reducing, branching, or closing pipe runs. This includes couplings, elbows, sleeves, tees, crosses, reducers, bushings, caps, plugs, nipples, unions, flanges, and similar fittings. Flanges that are designed for connecting pipe sections fall under this heading, regardless of whether they are forged, cast, or welded. The classification between 'forged' and 'not forged' at the statistical suffix level depends on the manufacturing process.
The distinction between 'not machined, not tooled and not otherwise processed after forging' and other flanges depends on whether significant material removal or surface finishing operations beyond basic trimming have been performed after the initial forging process. Basic operations such as trimming flash, shot blasting, or applying rust-preventive coatings do not constitute 'machining or tooling.' CNC machining of bolt holes, facing of sealing surfaces, or boring of bore holes to close tolerances would constitute machining after forging.
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