If you classify goods for import or export, you will run into both terms quickly, and they are easy to mix up. An HS code and an HTS code share the same starting point, but they are not the same thing. One is an international standard, the other is a national extension built on top of it. This guide explains what each one is, how the digits are structured, and why the distinction decides which code you actually file.
What an HS code is
HS stands for the Harmonized System, formally the Harmonized Commodity Description and Coding System. It is maintained by the World Customs Organization (WCO), a six-digit code used by more than 200 countries and economies to classify traded goods. The WCO updates the HS nomenclature roughly every five years. The current edition, HS 2022, took effect January 1, 2022, and the next revision — HS 2027 — is already in development.
Because every member applies the same six digits to the same goods, the HS is the shared international language of trade. When a product moves from one country to another, both customs administrations recognise the same six-digit subheading, even if everything after it differs. That shared base is what lets trade data, rules of origin, and preferential agreements line up across borders.
One nuance worth holding onto: the HS gives you the category, not the final answer. A six-digit subheading still covers a range of goods, and the country of import decides how that range splits into dutiable lines.
What an HTS code is
HTS stands for the Harmonized Tariff Schedule, a national extension built directly on the HS six digits. Each country takes the international six-digit base and adds further digits to capture its own duty rates and trade statistics. The United States version, the HTSUS, is administered by the U.S. International Trade Commission (USITC) and uses ten digits. Canada uses its Customs Tariff, which also extends to ten digits.
So an HTS code is really an HS code with a national tail. The first six digits are international and fixed; the remaining digits are country specific and tell that country's customs authority exactly how to treat the goods.
How the digits are structured
The Harmonized System is a hierarchy. Each pair of digits narrows the description, and the structure is the same everywhere up to the sixth digit:
- Digits 1 to 2 (Chapter). The broad category of goods, for example Chapter 09 for coffee, tea, and spices.
- Digits 3 to 4 (Heading). A more specific grouping within the chapter.
- Digits 5 to 6 (Subheading). The most precise level shared internationally. These six digits are the HS code, harmonized across all WCO members.
- Digits 7 to 8 and 9 to 10 (national tariff lines). Country-specific digits added by each nation for its own duty rates and statistics. These belong to the HTS, not the HS, and they can differ entirely between countries.
Read that way, the relationship is simple: the HS code is the first six digits, and the HTS code is the full national line that wraps around it.
| Attribute | HS code | HTS code |
|---|---|---|
| Issuing body | World Customs Organization (WCO) | The national authority (for example USITC in the US, CBSA-administered Customs Tariff in Canada) |
| Number of digits | Six | Typically eight to ten (ten in the US and Canada) |
| Scope | International, harmonized across more than 200 countries | National, specific to one country |
| Used for | A common classification language across borders | Setting duty rates, tariff treatment, and trade statistics |
HS vs HTS in Canada and the United States
In Canada, the national schedule is the Customs Tariff, a ten-digit schedule administered with the Canada Border Services Agency (CBSA). The first six digits match the WCO Harmonized System; the remaining four are Canadian tariff and statistical detail.
Canada's tariff landscape has gotten considerably more complicated over the past year and a half. Surtaxes on U.S.-origin goods, retaliatory measures, and remission orders have layered on top of the base tariff lines. As of August 2026, CBSA extended surtax remission for two additional months — the latest in a series of adjustments that have kept importers scrambling to keep up. The ten-digit code is just your starting point. You also need to know which additional measures apply to that code for that origin. If you're importing from the U.S. right now, the classification is only half the battle.
CBSA has also expanded its trade verification priorities this year to include a sharper focus on steel, aluminium, and trade agreement compliance. That means if your classification touches those product areas, the odds of a verification have gone up. Getting the code right matters more than it did two years ago.
In the United States, the national schedule is the HTSUS, also ten digits, published and maintained by the U.S. International Trade Commission (USITC). For US exports there is a related ten-digit export code, the Schedule B, administered by the Census Bureau, that classifies goods leaving the country. It shares the same first six HS digits but is used for export reporting rather than import duties.
Why the difference matters
The practical point is this: the first six digits travel across borders, but the things that cost you money, or stop a shipment, live in the national digits. Duty rate, tariff treatment, and admissibility are all determined by the full national tariff line, not the shared HS subheading.
That means you cannot import on an HS code alone. You must classify to the destination country's full national code: the HTSUS line for the United States, the Customs Tariff line for Canada. Getting the national digits wrong, even with a correct six-digit base, can mean the wrong duty, a rejected entry, or a costly correction later.
There's a real-world example making headlines right now that illustrates this perfectly. Canada is trying to collect $311 million in duties on chicken that was fraudulently labelled to misrepresent its U.S. origin. The classification codes were used to route product through the wrong tariff treatment. That's not a paperwork problem — that's a nine-figure enforcement problem. The first six digits give you a head start across markets, but they never finish the job in any single one of them.
Correct classification still runs on the General Interpretative Rules, which decide how a product is read into a heading and subheading before the national digits are even chosen. The resulting line is what flows into accounting systems like CARM in Canada, so a clean classification at the start keeps your duties, statistics, and audit records aligned downstream.
Where CustomsLogIQ fits
Knowing the difference is one thing; getting to the right ten-digit line on every product is another. CustomsLogIQ classifies a product to the full national tariff line, not just the six-digit HS base, with the GIR reasoning behind every decision and an audit trail you can defend. Instead of stopping at the harmonized six digits, you get the destination country's complete code, ready to file.