Tandom · Duty calculator
Add country and invoice value for the full duty stack — base + 301 + 232 + AD/CVD + fees.
HTS 8109.31.00.00 is the U.S. Harmonized Tariff Schedule classification for Containing less than 1 part hafnium to 500 parts zirconium by weight. It's a 10-digit statistical line in Chapter 81: Other base metals; cermets; articles thereof, Section XV: Base Metals and Articles of Base Metal, used by U.S. Customs and Border Protection to determine the duty rate at entry. No Chapter 99 tariff modifications (Section 301, Section 232, IEEPA) or AD/CVD orders currently flag this code in Tandom's catalog.
New to HTS codes? Read our guide on how HTS classification works →
HTS 8109.31.00.00 is the U.S. Harmonized Tariff Schedule classification for Containing less than 1 part hafnium to 500 parts zirconium by weight. It belongs to Chapter 81 of the HTSUS.
The general (Column 1) duty rate for HTS 8109.31.00.00 is Free. This is the most-favored-nation (MFN) rate that applies to imports from World Trade Organization member countries.
No active Chapter 99 tariff overlays (Section 301, Section 232, IEEPA reciprocal, etc.) currently flag HTS 8109.31.00.00 in Tandom's catalog. Use the calculator's date + origin inputs to confirm against any retroactive overlay you may be filing.
No active AD/CVD orders currently flag HTS 8109.31.00.00 in Tandom's catalog. Tandom monitors Federal Register notices daily; a flag will appear here within 24h of any new order's publication.
Section and chapter notes that govern this code
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.
Tandom guides relevant to this code
Where trade compliance APIs fit in a broker's filing pipeline: HTS classification, duty calculation, AD/CVD scope match, and post-summary corrections.
Open resource
Run thousands of product descriptions through HTS classification, score the confidence, and triage borderline rows. Public search endpoint plus the closed-beta three-layer Classifier.
Open resource
How to read, order, and report Chapter 99 HTS codes alongside the base classification on a US entry summary in 2026. The full stacking ladder for brokers and compliance teams.
Open resource
Why raw LLM prompts fabricate stat suffixes, why MCP-augmented prompts do not, and the prompt template a broker can hand to Claude or ChatGPT today.
Open resource
What changed for low-value DTC and ecommerce shipments after Section 321 de minimis was suspended in 2025. Filing, fees, and duty math through 2027.
Open resource
Turn a PDF commercial invoice into ACE-ready entry data. Which fields to extract, how to chain extraction into HTS classification and duty calculation.
Open resource