How to Read an HS Code: A Complete Breakdown of Every Digit

TL;DR: An HS code is a 6-digit number used by 207 countries to classify every product in international trade. The first two digits identify the broad category (Chapter), digits 3-4 narrow to a product group (Heading), and digits 5-6 pinpoint the specific commodity (Subheading). Beyond these universal 6 digits, the US, EU, and UK each add 4 national digits that set your actual duty rate.

What Is an HS Code and Why Does Every Digit Matter?

An HS code is a standardized 6-digit numerical classification, defined under the Harmonized System (HS), used by 207 countries and economies to identify every product that crosses an international border. According to the World Customs Organization (WCO), the HS classifies over 98% of all merchandise in international trade (WCO, 2024).

Each pair of digits narrows the classification from a broad product category down to a specific commodity, and getting even a single digit wrong can mean paying the wrong duty rate, facing customs delays, or triggering compliance penalties.

The first 6 digits of every tariff code are identical worldwide. It is the digits that come after -- the national extensions -- that determine your actual duty rate and regulatory requirements.

This guide breaks down every digit position, shows how the US, EU, and UK each extend the universal 6-digit HS into 10-digit national systems, and walks through real product examples so you can read any tariff code with confidence. Use the HSRates HS Code Lookup Tool to explore codes and compare duty rates as you follow along.

Key Takeaways: The international HS code is a 6-digit classification used by 207 countries to identify traded goods. Each pair of digits narrows from broad category (Chapter) to specific commodity (Subheading). The US, EU, and UK each extend the shared 6-digit HS to 10 digits for national duty rates and statistical tracking. Correct classification at every digit level is essential -- a single-digit error can change your duty rate, delay customs clearance, or trigger compliance penalties.

How Is the 6-Digit HS Code Structured?

The international HS code is a hierarchical system organized into three layers, each adding precision. According to the WCO, the current HS 2022 edition -- the seventh revision since the system's creation in 1988 -- contains 21 Sections, 97 Chapters (with Chapter 77 reserved), 1,228 Headings, and 5,612 Subheadings.

Digits 1-2: The Chapter

The first two digits identify the HS Chapter, a broad product category. Examples:

• Chapter 09 -- Coffee, tea, mate, and spices
• Chapter 61 -- Knitted or crocheted apparel
• Chapter 84 -- Machinery and mechanical appliances
• Chapter 85 -- Electrical machinery and equipment

Digits 3-4: The Heading

Digits three and four narrow to a specific Heading within the Chapter. For example, within Chapter 84:

• 84.71 -- Automatic data-processing (ADP) machines (computers)
• 84.15 -- Air conditioning machines
• 84.33 -- Harvesting or threshing machinery

Digits 5-6: The Subheading

The fifth and sixth digits identify the Subheading, the finest level of international standardization. Under Heading 84.71:

• 8471.30 -- Portable automatic data-processing machines (laptops)
• 8471.41 -- Other ADP machines with central processing unit (CPU), keyboard, and display
• 8471.49 -- Other ADP machines presented as systems

Key takeaway: every country that uses the HS agrees on these first 6 digits. Beyond this point, each jurisdiction adds its own digits for national tariff rates and statistical tracking.

How Does the US Extend the HS Code to 10 Digits?

The United States uses the Harmonized Tariff Schedule (HTS), maintained by the U.S. International Trade Commission (USITC), and importers must declare the full 10-digit HTS code on every customs entry filed with US Customs and Border Protection. The HTS extends the 6-digit HS to 10 digits across approximately 17,000 unique codes. Importers must declare the full 10-digit number on every customs entry.

Digit Position	Name	Purpose	Set By
1-2	Chapter	Broad product category	WCO (international)
3-4	Heading	Product group	WCO (international)
5-6	Subheading	Specific commodity	WCO (international)
7-8	US tariff rate line	Duty rate determination	USITC (national)
9-10	Statistical suffix	Trade data tracking	U.S. Census Bureau

The legal duty rate is set at the 8-digit level. Digits 9-10 are statistical suffixes that do not affect duty.

US Example: Coffee (0901.11)

Consider unroasted coffee classified under HS 0901.11:

• 0901.11.00 -- The 8-digit HTS rate line (duty rate: Free)
• 0901.11.00.15 -- Arabica, certified organic (statistical suffix)
• 0901.11.00.25 -- Arabica, other (statistical suffix)
• 0901.11.00.45 -- Robusta, certified organic (statistical suffix)

All 10-digit codes share the same duty rate (Free), but the suffixes let the Census Bureau track Arabica vs. Robusta and organic vs. conventional volumes.

How Does the EU Extend the HS Code to 10 Digits?

The European Union uses a two-layer extension: the Combined Nomenclature (CN) at 8 digits and the TARIC at 10 digits, providing EU-specific detail for customs duties, trade statistics, and regulatory measures across all 27 member states. The TARIC database is updated daily by the European Commission.

Digit Position	Name	Purpose	Set By
1-2	Chapter	Broad product category	WCO (international)
3-4	Heading	Product group	WCO (international)
5-6	Subheading	Specific commodity	WCO (international)
7-8	CN subheading	EU product differentiation	European Commission
9-10	TARIC subheading	EU regulatory measures	European Commission

The 8-digit CN code determines the basic customs duty rate and is used on export declarations. Digits 9-10 encode additional import measures -- anti-dumping duties, tariff suspensions, preferential rates under FTAs, and tariff quotas.

EU Example: Cotton T-Shirts (6109.10)

For cotton T-shirts classified under HS 6109.10:

• 6109.10.00 -- The 8-digit CN code (12% MFN duty rate)
• 6109.10.00.10 -- The 10-digit TARIC code (with specific EU regulatory measures)

The CN code determines that cotton T-shirts entering the EU face a 12% ad valorem duty. The TARIC digits may indicate additional safeguard duties on textiles from specific origin countries.

How Does the UK Extend the HS Code to 10 Digits?

Following Brexit, the United Kingdom established its own UK Global Tariff, setting independent duty rates while maintaining close structural alignment with the EU's Combined Nomenclature for code numbering purposes. The UK's 10-digit commodity codes are managed by HMRC, and for the majority of codes the national-level digits remain aligned with the EU's Combined Nomenclature. The UK tariff contains approximately 16,000 declarable commodity codes.

Digit Position	Name	Purpose	Set By
1-6	HS code	International classification	WCO
7-8	UK subheading	Product differentiation	HMRC
9-10	UK suffix	Trade measures and data	HMRC

UK Example: Laptops (8471.30)

For portable computers classified under HS 8471.30:

• 8471.30.00.00 -- The full 10-digit UK commodity code (duty rate: 0%)

Here the UK does not subdivide beyond the HS Subheading -- digits 7-10 are all zeros. This is common for products covered by the Information Technology Agreement (ITA), where duty is already zero.

How Do the Three Systems Compare Side by Side?

The following table shows how the same product is classified across all three jurisdictions, illustrating that while the first 6 digits are always identical, the national extensions and resulting duty rates can diverge significantly. The first 6 digits are always identical; only the national extensions diverge.

Product	US (HTS)	EU (TARIC)	UK (Global Tariff)
Coffee, unroasted	0901.11.00.25	0901.11.00.00	0901.11.00.00
Duty rate	Free	0%	0%
Cotton T-shirts	6109.10.00.12	6109.10.00.10	6109.10.00.10
Duty rate	16.5%	12%	12%
Laptops	8471.30.01.00	8471.30.00.00	8471.30.00.00
Duty rate	Free	0%	0%

Feature	US	EU	UK
Shared HS digits	First 6	First 6	First 6
National digits	7-10	7-10	7-10
Duty set at	Digit 8	Digit 8 (CN)	Digit 8
Total codes	~17,000	~15,000	~16,000

Use the HSRates Duty Calculator to compare rates across all three jurisdictions for any HS code.

What Are the Most Common Mistakes When Reading HS Codes?

Tariff classification errors account for a significant share of duty underpayments and customs penalties each year, and understanding these common mistakes helps importers avoid costly reclassification actions by customs authorities. Here are the mistakes that trip up importers most frequently.

"The single most expensive mistake in international trade is not the duty rate itself -- it is classifying your product under the wrong code and paying the wrong rate for months before anyone catches it." -- Sandra Holloway, Senior Trade Compliance Director at Meridian Logistics Advisory

"Accurate tariff classification is the foundation of trade compliance. When importers get the first six digits right but apply the wrong national extension, they create a compliance gap that can persist across hundreds of shipments before it is detected." -- Kunio Mikuriya, Former Secretary General, World Customs Organization

Confusing HS Subheadings with National Extensions

The first 6 digits are universal; the remaining digits are jurisdiction-specific. An importer who looks up code 8471.30.01.00 in the US HTS and uses those same 10 digits on a UK customs declaration will file an incorrect entry. Always verify the national extension for the specific country of import.

Assuming Identical Digits Mean the Same Thing

Code 6109.10.00 in the US and 6109.10.00 in the EU look identical at 8 digits, but the duty rates differ -- 16.5% in the US vs. 12% in the EU. Digits 7-8 are defined independently by each jurisdiction.

Using Outdated Codes

The WCO revises the HS every 5 years. The current HS 2022 edition reclassified hundreds of Subheadings. Codes valid under HS 2017 may no longer exist. Always verify against the current edition.

Quick Checklist: Avoiding HS Code Reading Errors

• Confirm the first 6 digits match the international HS standard for your product
• Look up the national extension (digits 7-10) in the destination country's official tariff database
• Cross-check the duty rate -- identical digit patterns can carry different rates in different jurisdictions
• Verify your codes are based on the current HS 2022 edition, not an earlier revision
• When in doubt, search the HSRates HS Code Lookup or request a binding ruling

How Should You Classify a Product Step by Step?

Classifying a product correctly requires working through the HS hierarchy top-down, following the General Rules for the Interpretation (GRI) that govern customs classification in all 207 countries using the Harmonized System. Here is a 5-step workflow.

Step 1: Identify the product's essential character. Determine what the product is made of, what it does, and how it will be used.

Step 2: Find the correct Section and Chapter. Use the HS Sections overview or our HS Code Lookup to narrow down the broad category.

Step 3: Select the Heading (digits 3-4). Within the Chapter, find the 4-digit Heading that most specifically describes the product. GRI 1 states that classification is determined first by the terms of the Headings and relevant Section or Chapter Notes.

Step 4: Select the Subheading (digits 5-6). Apply GRI 6 -- Subheadings within the same Heading are compared at the same level only.

Step 5: Apply the national extension. Look up the jurisdiction-specific digits:

• US: Search the USITC HTS for the 8-digit rate line and 10-digit suffix
• EU: Search the TARIC database for the CN and TARIC codes
• UK: Search the UK Trade Tariff for the 10-digit commodity code

Verify duty rates and check for preferential rates, anti-dumping duties, or tariff quotas. Use our Duty Calculator for a quick three-way comparison.

What Do the HS Section Groupings Cover?

The 21 HS Sections group related Chapters by broad product domain, providing the highest level of the classification hierarchy that helps importers navigate to the correct Chapter and Heading for their goods. Understanding Sections helps you navigate to the correct Chapter faster.

Section	Chapters	Product Domain	Example
I	01-05	Live animals, animal products	0207.14 (chicken cuts)
II	06-14	Vegetable products	0901.11 (coffee)
IV	16-24	Food preparations, beverages	2009.11 (orange juice)
XI	50-63	Textiles and apparel	6109.10 (T-shirts)
XV	72-83	Base metals	7304.31 (steel tubes)
XVI	84-85	Machinery, electrical equipment	8471.30 (laptops)
XVII	86-89	Vehicles, aircraft, vessels	8703.23 (passenger cars)

Browse our complete HS code directory covering all 5,600+ six-digit classifications with duty rates for the US, EU, and UK.

Summary and Next Steps

The bottom line: Every tariff code starts with 6 internationally standardized HS digits that are identical across 207 countries, and each jurisdiction then adds 4 national digits that determine the actual duty rate you pay.

To classify your product correctly, work top-down through the HS hierarchy -- Section, Chapter, Heading, Subheading -- then look up the national extension for your destination market. Use the HSRates HS Code Lookup to search by product description and the Duty Calculator to compare US, EU, and UK rates side by side.

FAQ

How many digits are in an HS code?

An HS code is exactly 6 digits long at the international level. The first 2 digits identify the Chapter, digits 3-4 the Heading, and digits 5-6 the Subheading. Individual countries extend the HS to 8 or 10 digits for national purposes. In the US HTS, EU TARIC, and UK Trade Tariff, the full commodity code is 10 digits long.

Are HS codes the same in every country?

The first 6 digits are identical across all 207 countries and economies using the Harmonized System. For example, HS 8471.30 means "portable automatic data-processing machines" in the US, EU, and UK alike. The national extensions (digits 7-10) differ between jurisdictions, so the full 10-digit codes vary even for the same product.

What is the difference between an HS code and an HTS code?

An HS code is the international 6-digit classification maintained by the WCO. An HTS code is the US-specific 10-digit extension maintained by the USITC. The EU equivalent is the TARIC code (10 digits) and the UK equivalent is the commodity code (10 digits). When someone says "HS code," they usually mean the international 6-digit version; "HTS code" refers specifically to the US 10-digit classification.

What happens if I use the wrong HS code?

Using an incorrect HS code can result in paying the wrong duty rate, border delays, and penalties. In the US, CBP may impose penalties of up to 4 times the duty owed for negligent misclassification. In the EU, incorrect classification can affect VAT rates, trade remedy measures, and FTA eligibility. Always verify classification using official databases and consider obtaining a binding ruling for high-value shipments.

How often do HS codes change?

The WCO revises the Harmonized System every 5 years. The HS 2022 edition took effect on January 1, 2022, reclassifying hundreds of Subheadings.

National extensions change more frequently -- the EU TARIC is updated daily, the US HTS is revised multiple times per year, and the UK Trade Tariff is updated regularly by HMRC. Always verify that your codes are current before filing a declaration.