What this United States estimate includes
ImportSmart separates the parts of the import calculation so you can inspect the rate, tax base, government fees and other shipment costs instead of receiving one unexplained total.
- Customs value based on the selected valuation method, goods value, freight and insurance.
- Base customs duty for supported simple HTS rates.
- Merchandise Processing Fee (MPF) for an applicable formal entry.
- Harbor Maintenance Fee (HMF) when the shipment and transport mode make it applicable.
- Supported China Section 301 and 2026 country-of-origin Section 301 layers.
- Freight, insurance, brokerage inputs and total landed-cost estimate.
The result is a planning estimate, not a binding customs decision, classification ruling or guarantee of the amount assessed at import.
What you need before calculating
Commodity code: Enter an 8- or 10-digit HTS code. A 6-digit heading is accepted only when every matching tariff line has the same simple ad-valorem rate.
- The country where the goods were manufactured or substantially transformed.
- The most specific HTS code you can verify for the product.
- Goods value, freight, insurance and shipment mode.
- Any confirmed exclusion, preference or special treatment that you choose in Advanced.
Start in Simple mode. Open Advanced only for a verified exception, preference, customs-valuation choice or manual tariff rate.
How the automatic tariff check works
Classification first. ImportSmart normalizes the HTS code and looks for a supported rate. It does not turn a specific rate such as cents per kilogram into an invented percentage.
Origin layers second. For U.S. imports, the selected country of origin can add or modify a Section 301 layer. China keeps its dedicated China 301 handling alongside the integrated origin rule.
Fees after duty. MPF and HMF are shown as separate components instead of being hidden inside one total. Verified preference or exemption controls stay under Advanced.
When ImportSmart stops instead of guessing
A visible stop is safer than a plausible-looking but unsupported duty figure. The automatic path asks for review when:
- The HTS line has a specific, compound, quota-dependent or conditional rate.
- A broad code matches tariff lines with different rates.
- A safeguard or exclusion requires facts that the product code alone cannot prove.
- The user has not confirmed an origin preference or exemption required by the rule.
Official tariff source
ImportSmart identifies the source used by the supported calculation path. For classification and final entry decisions, check USITC Harmonized Tariff Schedule directly.
Tariffs and trade measures can change. Confirm the commodity code, effective date, origin and any special treatment before relying on an estimate for a customs declaration or commercial commitment.
United States calculator questions
Does the calculator include Section 301 for goods from China?
Yes, the U.S. path retains the dedicated China 301 handling and also checks the integrated country-of-origin Section 301 layer. The product classification and any confirmed exclusion still matter.
Can I calculate with only a 6-digit HS code?
Only when all matching U.S. tariff lines resolve to one identical simple rate. If they do not, ImportSmart asks for an 8- or 10-digit HTS code instead of choosing a line for you.
Does a calculated result replace a customs ruling?
No. It is a planning estimate. Classification, origin, valuation, exclusions and entry facts should be confirmed with the official HTS and a qualified customs professional when needed.