Small importers spend 4-5 hours per transaction on tariff paperwork that used to take zero time, because tariff stacking makes duty calculation a multi-layer puzzle

A single import from China can now be subject to four or five overlapping tariff programs simultaneously: the baseline MFN/NTR duty, Section 301 tariffs (variable by HTS code, up to 100% on some products), Section 232 tariffs (25% on steel and aluminum), fentanyl tariffs (10-20%), and reciprocal tariffs (10%). These do not simply add up — Executive Order 14289 established complex stacking rules where some tariffs apply cumulatively and others are applied as the higher-of. One CEO of a medical supply company reported going from spending zero time on tariff paperwork to 4-5 hours per transaction. This matters because small businesses do not have trade compliance departments. A five-person company importing components from Shenzhen now needs to determine: which Section 301 list their product falls under (there are four lists with different rates), whether any exclusions apply (178 product-specific exclusions existed through November 2025), whether the product is also subject to Section 232 (steel/aluminum content), how the fentanyl tariff interacts with the reciprocal tariff, and whether any of these have been modified by subsequent executive orders. Getting it wrong means either overpaying duties (directly reducing margin) or underpaying duties (risking penalties of up to 4x the unpaid amount for gross negligence). The American Action Forum found that small businesses with fewer than 50 employees paid on average $86,000 more in tariffs during a six-month period in 2025 than the prior year. The root cause is that the U.S. tariff system was designed for a world where Congress sets tariff rates through legislation — a slow, deliberate process. When the executive branch imposes tariffs through multiple overlapping emergency authorities (IEEPA, Section 301, Section 232, Section 201), each with its own scope, exclusion process, and stacking rules, the result is a compliance environment so complex that even licensed customs brokers struggle to calculate the correct duty rate. There is no single authoritative calculator or API that takes an HTS code and country of origin and returns the total effective duty rate across all programs.