How do you calculate landed cost with duty, MPF and HMF?

What value are customs duty and fees calculated on?

Duty, MPF and HMF are all charged on the same base: the customs value set by section 1401a of Title 19 of the US Code, which for most parts is the transaction value. That value excludes international freight and insurance but adds certain costs the buyer pays outside the invoice.

The statute defines the price actually paid or payable as the total payment for the goods, exclusive of transportation, insurance and related services incident to the international shipment (19 U.S.C. 1401a(b)(4)). In practice that means the US uses a value close to the price at the export port, not a value that includes the ocean leg. If your supplier quotes a delivered price, the broker has to back out the freight and insurance, which requires those amounts to be shown separately.

The same section then adds five items to the price when they are not already in it: packing costs paid by the buyer, selling commissions, assists, royalties or license fees required as a condition of sale, and resale proceeds that flow back to the seller. For buyers of cast parts, assists are the one that matters. The statute lists tools, dies, molds and similar items supplied by the buyer free or at reduced cost as an assist, along with engineering and design work done outside the US (19 U.S.C. 1401a(h)(1)). So if you pay for a die-casting die on a separate invoice, its value is apportioned into the customs value of the castings it makes, and duty and fees are owed on it. How the apportionment is done is a question to settle with your broker before the first entry, not after an audit.

Three consequences follow for parts buyers. First, small formal entries pay the floor, so a trial shipment of castings worth a few thousand dollars carries a fee that is a much larger share of its value than the headline rate suggests. Second, the ceiling makes MPF almost free in percentage terms on very large entries, which is one reason consolidating shipments onto fewer entries can pay. Third, informal entry is available for most shipments valued at $2,500 or less, with exceptions for certain Chapter 99 goods (19 CFR 143.21); check with your broker before assuming a sample shipment qualifies.

MPF does not apply to goods that qualify as originating under several US free trade agreements, including USMCA, Singapore, Chile and Australia, among others listed in paragraph (c) of the regulation (19 CFR 24.23(c)). The US has no such agreement with China or Vietnam, so parts from either country pay MPF in full.

How do Chapter 99 duties change landed cost for parts from China or Vietnam?

They are usually the largest duty line and the only one that depends on country of origin, because the HTS code and its general rate stay the same wherever the part is made. Look them up for the exact code, origin and entry date, since they change far more often than MPF or HMF.

Chapter 99 of the tariff schedule holds the temporary and additional duties, and in September 2026 a metal-parts buyer should check three layers. The first is Section 301. Goods of China still carry the older China-specific Section 301 lines (USTR Section 301 tariff actions). On top of that, since July 24, 2026 a newer Section 301 action covers products of about 60 economies, Vietnam and China among them, at 10 or 12.5 percent depending on USTR’s finding for each economy (USTR notice, Federal Register, July 28, 2026). For China and Vietnam the rate is a flat 12.5 percent; for some other economies, such as the European Union and Taiwan, it is set net of the general rate instead of added to it. So, for a code outside Section 232, a Vietnamese part carries the new tier alone, and a Chinese part carries both. The second layer is Section 232 on aluminum and steel, including derivative articles listed in Chapter 99. Goods that fall under Section 232 are exempted from the new Section 301 tier by the annexes to that notice, so check which one applies to your code rather than adding both. The third layer is anything else issued by proclamation or executive order.

The timeline matters when you reuse an old spreadsheet. The reciprocal duties imposed in 2025 under the International Emergency Economic Powers Act were ended in February 2026 by an order that keeps Section 232 and Section 301 in place (Executive Order 14389). A 10 percent surcharge under Section 122 of the Trade Act of 1974 took their place, limited by statute to 150 days (Proclamation 11012). It expired on July 24, 2026, the day the new Section 301 tier began, so an entry today should show no Section 122 line. A 2025 order also set a separate penalty for goods found to be transshipped to evade duties (Executive Order 14326); this guide cannot confirm how that provision stands today, so read it with your broker. The tariffs and origin page sets out the current rates by origin.

For parts from China or Vietnam, every one of these duties that applies is charged on the customs value, like the general rate, so they add up; the exception is the Section 232 exemption above. In a landed-cost sheet, give each its own line with its legal basis, rather than one blended “tariff” percentage that nobody can audit later. Origin itself follows where the part was substantially transformed: a part cast and machined in Vietnam is a Vietnamese product, while one only finished or repacked there generally is not.

Two sensitivities are worth running before you send the comparison to finance. Drop the same parts to a trial lot worth $6,000 and MPF rises to the $34.58 floor per CBP Dec. 26-14, well above what the rate alone would give. Put the die on the buyer’s separate invoice and the die’s apportioned value joins V, raising duty, every Chapter 99 line, MPF and HMF together.

The customs lines are only as good as the part data behind them. The HTS code comes from what the part is and does, and the value comes from a clean quote that shows part price, tooling, packing and freight separately. The RFQ preparation guide lists what to send so a supplier can quote in that shape, and our die casting and CNC milling pages show the part families we source from partner foundries and machine at our lead CNC plant; each quote states the production site and country of origin.