Data Sources & Coverage
TariffBase provides tariff data sourced exclusively from official government and customs authority publications. This page explains where our data comes from, how it is processed, how often it is updated, and what quality measures we apply.
Data Philosophy
TariffBase follows three core principles for data management:
- Official sources only -- All tariff data originates from government customs authorities or their designated publications. We never rely on third-party aggregators, unofficial databases, or crowd-sourced information.
- Human-verified quality -- While our data pipeline includes automated collection and processing, every dataset is reviewed by human analysts before publication.
- Transparency -- Every tariff rate in TariffBase includes effective dates and source references, so you can trace any data point back to its official origin.
Market Coverage
TariffBase currently covers three major trading markets:
United States
| Attribute | Detail |
|---|---|
| Data source | US International Trade Commission (USITC), Harmonized Tariff Schedule of the United States (HTSUS) |
| Schedule structure | 10-digit HTS codes |
| Regimes covered | MFN (Column 1 General), Column 2, Section 201 safeguards, Section 232 national security, Section 301 (China stages), IEEPA additional tariffs, FTA rates (USMCA, etc.) |
| Special measures | Anti-dumping duties, countervailing duties, additional tariffs by country of origin |
European Union
| Attribute | Detail |
|---|---|
| Data source | TARIC (Integrated Tariff of the European Communities), maintained by the European Commission |
| Schedule structure | 10-digit TARIC codes covering all 27 EU member states |
| Regimes covered | MFN (Third country duty), Customs Union rates, GSP, GSP+, EBA (Everything But Arms), bilateral FTA rates, autonomous tariff suspensions, tariff quotas |
| Special measures | Anti-dumping duties, countervailing duties, safeguard measures, additional duties by partner |
China
| Attribute | Detail |
|---|---|
| Data source | China Customs Tariff Commission, Ministry of Finance, General Administration of Customs |
| Schedule structure | 10-digit national tariff codes |
| Regimes covered | MFN rates, provisional (temporary) rates, conventional (FTA) rates, retaliatory additional tariffs |
| Special measures | Retaliatory tariffs against specific partners, anti-dumping duties, countervailing duties |
Data Coverage Statistics
The TariffBase database contains:
- Tariff lines -- The total number of distinct product classifications (national HS codes) for each country
- Regimes -- The number of distinct tariff regimes applied by each country (MFN, preferential, additional, etc.)
- Tariff rates -- The total number of individual rate entries across all products and regimes
Current statistics are displayed on the Dashboard in the Our Tariff Data panel.
Data Processing Pipeline
Our data goes through a structured pipeline from source to platform:
1. Collection
Tariff data is collected from official government websites, customs databases, and gazette publications. Our collection process monitors these sources for updates, including:
- Scheduled annual tariff revisions
- Mid-year amendments and corrections
- Emergency tariff actions (e.g., retaliatory measures, executive orders)
- New trade agreements entering into force
2. Parsing & Structuring
Raw data from different countries comes in various formats (PDFs, spreadsheets, HTML tables, database exports). We parse and transform this data into a unified, harmonized structure that enables:
- Consistent code hierarchy display across all markets
- Comparable rate presentation regardless of the source format
- Proper linking between regimes, partner countries, and tariff rates
3. Validation & Quality Assurance
Every dataset update goes through quality checks:
- Automated validation -- format checks, rate range verification, code structure validation
- Cross-reference checks -- comparison against previous versions to identify unexpected changes
- Human review -- analysts verify key data points, especially for complex measures like duty stacking and multi-regime products
4. Publication
Once validated, updated data is published to the platform. The Last Update date shown in search results reflects when each specific tariff entry was last refreshed.
Update Frequency
| Update Type | Typical Frequency |
|---|---|
| Annual tariff revisions | Processed as each country publishes its new schedule (typically January 1 for most countries) |
| Major tariff actions | Processed within days of official announcement (e.g., new Section 301 lists, retaliatory measures) |
| Routine amendments | Processed on a regular schedule as countries publish corrections and adjustments |
| Trade agreement updates | Processed as new FTAs or rate changes under existing agreements enter into force |
Note: During periods of heightened trade tension (such as active trade disputes), updates may be more frequent to capture rapidly evolving tariff actions.
Data Limitations
While TariffBase strives for comprehensive and accurate coverage, users should be aware of the following:
- VAT and GST are excluded. TariffBase covers customs duties only. Value-added tax, goods and services tax, and other domestic consumption taxes are not included in rate calculations.
- Non-tariff measures are not covered. Import licensing requirements, quotas, sanitary/phytosanitary measures, and technical barriers to trade are outside the scope of TariffBase data.
- Anti-dumping and countervailing duty rates may apply to specific companies or product variants. TariffBase shows general rates where available but may not cover company-specific rates.
- National extensions may vary. While the 6-digit HS code is international, the 8-digit and 10-digit extensions are country-specific. Always verify that you are using the correct national code for your destination market.
- This is not legal advice. TariffBase data is provided for informational and decision-support purposes. For legally binding tariff classifications or rate confirmations, consult your national customs authority or a licensed customs broker.
Effective Dates & Historical Data
Every tariff rate in TariffBase is associated with an effective date indicating when the rate became or becomes applicable. This allows you to:
- Verify that you are looking at the currently applicable rate
- Understand when specific tariff actions took effect
- Track rate changes over time via the Regulatory Tracker
Feedback & Corrections
If you identify a data discrepancy or have questions about a specific tariff rate:
- Contact our support team with the specific tariff code, country, and the issue you observed.
- Our data team will investigate and, if confirmed, issue a correction promptly.
We take data quality seriously and appreciate user feedback as part of our continuous improvement process.