Classification starts by identifying the article's material composition, function, and state of assembly, then walking the Harmonized Tariff Schedule from the 6-digit international heading down to the full 10-digit US statistical suffix — the last four digits are US-specific and determine the exact duty rate and any statistical reporting requirements. General Rules of Interpretation (GRI 1–6) govern how to break ties between competing headings, and CBP binding rulings on similar products from Hong Kong or comparable origins are a useful sanity check before filing. Misclassification is the single most common cause of delayed entries and post-entry penalties, so verifying the code before your first shipment — not after CBP flags it — is worth the time.

Before the suspension, shipments from Hong Kong valued under $800 could clear US customs duty-free with minimal paperwork, which is what made direct-to-consumer drop-shipping and small-parcel fulfillment models economically viable at scale. With that exemption suspended and written into federal regulation (19 CFR 10.151 and 19 CFR 145.31) effective June 24, 2026, every shipment now needs a real customs entry and full duty payment regardless of value, which pushes per-unit landed cost up and makes bulk formal-entry importing with domestic US fulfillment relatively more attractive than high-volume low-value parcel shipping.

Informal entry (Entry Type 11) applies to shipments valued at $2,500 or under with no antidumping/countervailing, quota, or PGA complications — it requires less paperwork and no customs bond, and can often be self-filed or handled quickly by a broker. Formal entry (Entry Type 01) is required above that $2,500 threshold, or whenever AD/CVD orders, quota categories, or Partner Government Agency review apply regardless of value, and it requires a customs bond (single-entry or continuous) plus a more complete entry package — commercial invoice, bill of lading, and supporting classification documentation. Hong Kong does not carry a blanket preferential program in our dataset, so this calculator's 3.9% baseline reflects a standard MFN starting point pending your product's exact HTS classification.

CBP requires all formal and most informal entries to be transmitted electronically through the Automated Commercial Environment (ACE), which in practice means working with a licensed customs broker who holds ACE filer credentials, or self-filing if you hold your own CBP-approved ACE account and bond. The filer submits the entry summary, HTS classification, customs value, and any PGA data electronically before or on arrival, and ACE returns a release determination — usually within minutes for low-risk formal entries with clean documentation. For a new import lane from Hong Kong, it's worth confirming your broker's ACE filer code and bond coverage before the first shipment departs, rather than discovering a gap once cargo is already in transit.