Guides
How U.S. import tariffs are calculated, which layers apply to your HTS code, and how to get the paperwork right — each guide ends with a worked example you can rerun in the calculator.
- How Is a U.S. Import Tariff Calculated in 2026?
The U.S. tariff formula: customs value × each applicable rate (MFN + Section 301/232/338) + MPF/HMF fees, added without compounding — with a worked HTS example.
- Section 301 Tariffs on China in 2026: Lists, Rates & Exclusions
Section 301 tariffs on China in 2026: Lists 1–4A rates (25% / 7.5%), four-year review increases, the July 24 global 301 tier, and the exclusion window to Nov 10.
- Who Actually Pays Tariffs — Importer or Exporter?
Who actually pays U.S. import tariffs: the importer of record remits duty to CBP, but who bears the cost depends on the Incoterm, the contract and the market. DDP vs DAP explained.
- Proforma vs Commercial vs Customs Invoice: Which One Customs Wants
Proforma vs commercial invoice vs customs invoice: what each document is for, when CBP accepts them, whether you can pay a proforma, and which one your shipment actually needs.