USITC HTS Reststop API: Endpoint Reference, Limits, and a Production Alternative

What Is the USITC Reststop API?

The United States International Trade Commission (USITC) publishes the Harmonized Tariff Schedule of the United States (HTSUS) as a free REST API at https://hts.usitc.gov/reststop. It requires no authentication and covers all 99 HTS chapters.

If you found this page because you are building a trade compliance integration and need HTS data programmatically, this reference documents every endpoint, parameter, and response field the USITC API exposes — along with its limitations and how TradeFacts.io compares.

Base URL

https://hts.usitc.gov/reststop

All endpoints are unauthenticated HTTP GET requests. The API returns JSON.

Endpoints

GET /searchByNumber

Look up a specific HTS code by number.

GET https://hts.usitc.gov/reststop/searchByNumber?query=8471.30.01.00
GET https://hts.usitc.gov/reststop/searchByNumber?query=0101.21.00.10

Parameters:

query — Full or partial HTS number (required). Supports prefix matching.
release — Optional. Specific schedule release (e.g. 2024BasicDec). Defaults to current.

Response fields: htsno, indent, description, unit1, unit2, general, special, other, footnotes, quota_quantity, additional_duties.

GET /searchByDescription

Full-text keyword search across HTS descriptions.

GET https://hts.usitc.gov/reststop/searchByDescription?query=aluminum+wire
GET https://hts.usitc.gov/reststop/searchByDescription?query=semiconductor

Parameters:

query — Keyword string (required). Space-separated terms are treated as AND.
release — Optional. Specific schedule release.

GET /releaseList

Returns the list of all available schedule releases.

GET https://hts.usitc.gov/reststop/releaseList

Response is a JSON array of release identifiers (e.g. ["2024BasicDec", "2024BasicJun", ...]). Use these values in the release parameter of other endpoints.

GET /getChapter

Returns all HTS records for a given chapter number.

GET https://hts.usitc.gov/reststop/getChapter?chapter=84
GET https://hts.usitc.gov/reststop/getChapter?chapter=01

Parameters:

chapter — Two-digit chapter number, zero-padded (required).
release — Optional. Specific schedule release.

Chapter responses can be large — Chapter 84 (machinery) returns several hundred records.

Response Format

All endpoints return a JSON object with an HTSDataSet array:

{
  "HTSDataSet": [
    {
      "htsno": "8471.30.01.00",
      "indent": "2",
      "description": "Portable automatic data processing machines...",
      "general": "Free",
      "special": "Free (A,AU,BH,CL,CO,D,E,IL,JO,...)",
      "other": "35%",
      "unit1": "No.",
      "unit2": "",
      "footnotes": "",
      "quota_quantity": "",
      "additional_duties": ""
    }
  ]
}

Heading nodes — short codes like 8471 that represent category headers — appear in results with empty rate fields. Actual duty rates exist only on leaf (10-digit) codes.

Known Limitations

These are the production pain points most engineering teams hit after their initial prototype.

No change detection. There is no endpoint to tell you what changed between releases. To detect HTS updates you must download two full releases and diff them yourself.
US-only. There is no Canadian Customs Tariff equivalent. Teams needing cross-border data — CUSMA/USMCA preferential rates, Canadian MFN rates — must source and maintain that dataset separately.
Unstructured additional duties. Section 301, 232, and 201 surcharges appear as unstructured text in additional_duties or folded into special. Parsing them programmatically requires regex work and ongoing maintenance as tariff actions evolve.
No published SLA. The API has no uptime guarantee. Teams have reported intermittent 500 errors, particularly around USITC schedule publication dates.
No webhooks or push notifications. You must poll to detect schedule changes.
Release lag. New schedule releases appear on the API with a delay after the official USITC publication date.

How TradeFacts.io Compares

TradeFacts.io is a commercial HTS and Canadian Customs Tariff API built for production trade compliance software. Here is how it maps to the USITC reststop endpoints:

Capability	USITC Reststop	TradeFacts.io
US HTS lookup by code	✓ `/searchByNumber`	✓ `GET /api/hts/{code}`
US HTS keyword search	✓ `/searchByDescription`	✓ `GET /api/search?q=`
US HTS by chapter	✓ `/getChapter`	✓ `GET /api/chapter/{n}`
Canadian Customs Tariff	✗ Not available	✓ `GET /api/ca/{code}` (Tier 2+)
CUSMA/UST preferential rates	✗ Not available	✓ Included in all CA records
Nightly change detection	✗ Manual diff required	✓ `GET /api/changes`
Webhooks on tariff changes	✗ Not available	✓ HMAC-signed (Tier 3)
Uptime SLA	✗ None published	✓ 99.5% target
Cost	Free	From $199/month after 30-day free trial

Quick Start: Migrating from USITC to TradeFacts.io

The endpoint mapping is straightforward. Request a free trial key at tradefacts.io/contact.html and swap the URLs:

# USITC: lookup by code
curl "https://hts.usitc.gov/reststop/searchByNumber?query=8471.30.01.00"

# TradeFacts: same lookup
curl -H "X-API-Key: YOUR_KEY" \
     "https://tradefacts.io/api/hts/8471.30.01.00"

# USITC: keyword search
curl "https://hts.usitc.gov/reststop/searchByDescription?query=aluminum+wire"

# TradeFacts: same search
curl -H "X-API-Key: YOUR_KEY" \
     "https://tradefacts.io/api/search?q=aluminum+wire"

# TradeFacts only: Canadian Customs Tariff
curl -H "X-API-Key: YOUR_KEY" \
     "https://tradefacts.io/api/ca/search?q=aluminum"

# TradeFacts only: what changed since last USITC update?
curl -H "X-API-Key: YOUR_KEY" \
     "https://tradefacts.io/api/changes"

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