HTS codes without the jargon
Every product that enters the US gets a ten-digit code, and that code decides the duty rate. That's the whole idea. Everything else — the chapters, the headings, the notes — is machinery for picking the right code. You don't need to classify goods yourself, but you do need to know enough to sanity-check what lands on your customs invoice.
What an HTS code is
The Harmonized Tariff Schedule is the master list: thousands of product categories, each with a code and a duty rate. The first six digits are international, shared with every other country that uses the system. The last four are US-specific. A code like 8714.99.80 reads as: Chapter 87 (vehicles), heading 8714 (bicycle parts), then increasingly specific US subdivisions. You can search the whole schedule free on the USITC website — our calculator searches it for you when you type what you're importing.
Why one digit matters
Adjacent codes can carry wildly different rates. A leather handbag and a plastic one sit in different subheadings. A part "of" a machine and a part "suitable for" a machine can land in different chapters. A one-digit difference in the wrong position can swing the base duty from 0% to 25% — and the special tariffs stacked on top often key off the same code. Classification is the single biggest lever in your duty bill, and it's set by whoever typed the entry, often at speed.
Classification drift
The schedule is revised roughly three times a year. Codes get split, merged, and re-described. A code that was correct when you onboarded the SKU can be wrong eighteen months later — and nothing in your system tells you it changed. This drift is now a leading cause of duty overpayment, in both directions: companies paying too much on a dead code, and companies paying too little on a code that quietly moved into a tariffed list.
The audit math
CBP can audit back five years on classification errors, and penalties for negligent misclassification can reach four times the lost duties — more for gross negligence or fraud. A small per-entry error on a steady SKU compounds into a large number over sixty months of entries. This is why "the broker has always used this code" is not a control.
What you can check yourself
- Pull the codes off your entry summaries (CBP Form 7501, or your broker's reports) and list what you're actually being filed under, per SKU.
- Compare against the USITC schedule — does the description still match your product, and does the rate match what you were charged?
- Watch for splits. Two SKUs your supplier treats as one product can belong in different headings, at different rates.
When to confirm with a licensed broker
Self-checks are for sanity, not for filing. Confirm with a licensed customs broker when a product is new, when a code's rate looks wrong, when the schedule revision touched your chapter, or when the dollars at stake justify a binding ruling from CBP. Brokers classify for a living; a second look costs far less than a five-year lookback.