Landed Cost · research

Is the 6-digit HS code enough to estimate U.S. duty?

For the general duty rate, usually yes: three quarters of the 8- and 10-digit numbers the U.S. schedule lists carry their 6-digit subheading's most common rate. For apparel, footwear and a handful of other chapters, no. And for the additional duties — Section 301, Section 232, anti-dumping — the 6-digit code is never the whole answer. Here is the measurement.

What we measured

The U.S. schedule publishes duty rates at the 8- and 10-digit tariff line. Every one of those lines sits under an internationally shared 6-digit HS subheading. So the question is simple: if you only know the six digits, how much of the general (Column 1) rate do you already know?

The 5,612 subheadings match the count the World Customs Organization states for the HS 2022 edition (compared by count, not code by code). USITC Harmonized Tariff Schedule, snapshot dated 2026-09-14, measured 2026-09-14. Counts are per subheading and per tariff line — not weighted by import value, so a rarely used line counts as much as a common one.

Where six digits are not enough

The wide subheadings are not spread evenly. They cluster in a few chapters — apparel, footwear and bags among them.

The widest spreads in the schedule are in tobacco, where subheadings 2401.10, 2401.20 and 2401.30 carry percentage rates from Free to 350%. In footwear, subheading 6402.99 has 65 tariff lines with 10 different published rates, its percentage rates running from 3% to 48%. No range that wide is useful for pricing a product, and a responsible estimate says so instead of averaging it.

The duties six digits can never tell you

The general rate is only the first layer. The others are set by the product's origin, by lists published at the full tariff line, or by the specific exporter — so they need more than the subheading, and some need more than any code.

Official sources: the USITC tariff schedule, CBP's guidance on the Section 301 forced-labor duties, and Commerce's AD/CVD records.

Where planning ends

Six digits are enough to plan a price, compare suppliers and decide whether a product is worth a closer look. They are not a classification for a customs entry. Our tool stops at six digits by design; the tariff line for an actual shipment is a licensed customs broker's determination. For certainty on a specific product, CBP publishes its past classification rulings in the free CROSS database and issues binding rulings on request.

One real estimate

A plain cotton t-shirt from China, as the API answered it on 2026-09-15 — selected fields, values unedited.

{
  "hs_code": "6109.10",
  "description": "T-shirts, singlets, tank tops and similar garments, knitted or crocheted > Of cotton",
  "duty_estimate": {
    "min_pct": 16.5,
    "max_pct": 16.5,
    "most_common_rate_text": "16.5%",
    "tariff_lines_in_subheading": 15,
    "precision_note": "All 15 8- and 10-digit U.S. numbers listed under this subheading carry the same published general rate (16.5%), so this estimate is not a range — it is the rate for the whole subheading. It is still not an entry classification. These figures are General (Column 1) rates only: they EXCLUDE Section 301 and Section 232 additional duties, AD/CVD, and every other additional duty (see surcharge_coverage)."
  },
  "surcharge_coverage": "Section 301, China lists: every duty-rate line under this subheading appears on one or more of the China Section 301 lists (Lists 1, 2, 3 and 4A, U.S. Note 20); see applicable_surcharges. Product-specific USTR exclusions are NOT applied here. Section 301 forced-labor action: NOT ASSESSED for any origin. Effective 2026-07-24, it imposes duties of 10% or 12.5% on products of 60 economies, China included (for China, in addition to the China lists above; for EU member states, Japan, South Korea, Switzerland and Taiwan, as a combined rate with the column 1 rate), under the 9903.05 headings of HTSUS Chapter 99, subject to the exemptions in U.S. Note 52. Verify at https://content.govdelivery.com/accounts/USDHSCBP/bulletins/421d887 (CBP guidance \"Section 301 Forced Labor Import Duties\", issued 2026-07-23, read 2026-09-11). Section 232: NOT ASSESSED for any origin. Section 232 duties are product-specific and are not in this estimate; verify at cbp.gov. No other Section 301 action is assessed either. AD/CVD: NOT ASSESSED for any origin. Antidumping and countervailing duties are specific to the product, the country and the exporter, can far exceed the general rate, and are not in this estimate, so nothing here indicates whether an order applies; verify at access.trade.gov.",
  "tariff_schedule_snapshot": "2026-09-14"
}

Try a description of your own: the free landed-cost estimator takes plain English and returns the subheading, the rate range with its width stated, and the lines it did not assess. The same thing is available as an API.

A separate question: can the six digits be got right in the first place?

Everything above assumes you already have the correct subheading. Getting there is its own problem, and we measured ourselves on it: given the merchandise descriptions from 100 of CBP's published binding rulings, our own classifier matched CBP's 6-digit subheading 23.5% of the time, the 4-digit heading 38%, the chapter 58% — Six digits against CBP's own rulings, with every miss and the full test set published. Binding rulings are hard cases by construction, so that is not a rate for everyday goods; it is, however, the reason this page says a duty range rather than a duty.

Part of why it is hard has nothing to do with any classifier: across 140 of those rulings, a keyword search of the tariff schedule never surfaces the correct heading at all for 4–10% of products, because the schedule and the seller describe the same object in different words — a winemaking system belongs under machinery for the preparation of “drink”, cremation urns under “ornaments”. The headings a keyword search can never find has the measurement and the data.

What this does not prove

It measures the general rate only, per subheading and per line, on one snapshot of the schedule. It says nothing about how often a given business's actual imports fall in the wide subheadings — that depends on what you import — and nothing about the additional duties beyond which ones a six-digit code cannot settle.

Download the data

Every measured figure on this page comes from these files, recomputed from the same schedule snapshot. They are free to reuse under CC BY 4.0 with attribution to Aervik Labs.

hts-duty-spread-by-subheading.csv — one row per subheading: its lines, distinct rates, most common rate, percentage range and spread.

hts-duty-spread-by-chapter.csv — the chapter counts behind the table above, for every chapter.

hts-duty-spread-summary.json — the headline figures.

README.txt — columns, method, limits and how to cite.

How lines are counted: every 8- and 10-digit number the schedule lists counts as a tariff line, so an 8-digit line listed with 10-digit statistical suffixes is counted alongside each of them. Counting only 8-digit lines, 68.8% (7,849 of 11,414) carry the most common rate in their subheading. A subheading's spread covers its percentage rates only, and 242 subheadings also carry a specific or compound rate. The README gives all three line counts.

Release and corrections

This release is computed from the schedule snapshot dated 2026-09-14. Corrected 2026-09-14: the first release, computed from the 2026-09-02 snapshot, was built on a schedule export that cut each General rate text longer than 40 characters to 40, and each description longer than 180 characters to 180, so those rate texts and descriptions in the files ended mid-word. Rebuilt from a complete export, tariff lines carrying their subheading's most common rate moved from 17,522 to 17,502 and subheadings with one identical rate from 4,046 to 4,044; no percentage on this page changed. The README's release history records the correction and the headline figures that moved.

Suggested citation

Aervik Labs (2026). U.S. General Duty Rate Spread Within 6-Digit HS Subheadings (release 2026-09-14) [Data set]. Derived from the USITC Harmonized Tariff Schedule, snapshot dated 2026-09-14. CC BY 4.0. https://aerviklabs.com/guides/is-the-6-digit-hs-code-enough/

@misc{aervik_hts_duty_spread,
  author       = {{Aervik Labs}},
  title        = {U.S. General Duty Rate Spread Within 6-Digit HS Subheadings},
  year         = {2026},
  version      = {2026-09-14},
  howpublished = {Data set, CC BY 4.0},
  note         = {Derived from the USITC Harmonized Tariff Schedule, snapshot dated 2026-09-14},
  url          = {https://aerviklabs.com/guides/is-the-6-digit-hs-code-enough/}
}