Most zinc die cast parts clear customs under HS heading 7907 as “other articles of zinc”, but a large number do not — they are classified as parts of the machine they belong to, which can change the duty rate by several percentage points. Getting the code wrong is one of the few importing mistakes that is both easy to make and expensive to unwind.
The rest of the landed cost story is more mundane and more frequently underestimated: freight, duty stacking, brokerage and the quality risk that shows up after the container is opened. This is how the numbers fit together, and which decisions belong to you rather than to your supplier.
Why the HS code is not as simple as “zinc”
Chapter 79 of the Harmonized System covers zinc and articles of zinc. Heading 7907 is the residual heading for other articles of zinc, and it is where a plain cast fitting with no more specific home usually lands.
But the HS is function-first, not material-first. If a zinc casting is identifiably a part of a specific machine — a component of a lock, a pump, a motor, a vehicle — it may belong in the heading for that machine’s parts rather than in Chapter 79. Section XVI, which covers machinery, has its own rules about when a part is classified with the machine and when it falls to a residual parts heading.
Two consequences. First, the same casting can carry different codes depending on what it is sold as: a die cast zinc housing sold as a generic casting is not the same article, for tariff purposes, as the same housing sold as a spare part for a specific pump. Second, the finished-ness matters. A casting that has been machined, threaded and plated into a finished component is a different classification question from a raw casting.
| Situation | Likely classification |
|---|---|
| Zinc casting, no specific machine identity | 7907 — other articles of zinc |
| Machined and finished hardware (handles, fittings) | Usually 7907, sometimes 8302 for certain hardware |
| Identifiable part of a specific machine | Parts heading of that machine’s chapter |
| Part of a vehicle | Chapter 87 parts heading, not Chapter 79 |
| Electrical connector or terminal | Chapter 85, by function |
This table is a starting point for the conversation with your broker, not a ruling. Classification disputes are settled by tariff rulings, and both the EU and the US have formal mechanisms: Binding Tariff Information in the EU, valid for three years, and a customs ruling from CBP in the United States. If a part is high-value or high-volume, a ruling is cheap insurance.
Duty is only one of five cost lines
Landed cost is the sum of things that are easy to see and things that are not. The visible ones are the unit price and the freight. The invisible ones are where budgets go wrong.
Customs duty. Ad valorem on the customs value, which is normally the transaction value plus international freight and insurance to the border. The rate depends entirely on the code and the origin.
Additional duties. The United States applies additional tariffs under Section 301 to many China-origin products, identified by specific HTSUS subheadings. Whether your part is caught depends on the code, not on the fact that it is a casting. This is worth checking line by line, because two similar parts can sit on different sides of the line.
Import VAT or sales tax. In the EU, import VAT is charged at the destination country rate and is recoverable for a VAT-registered importer — so it is a cash flow item, not a cost. In the US there is no import VAT, but state sales and use tax rules apply to the subsequent sale. Buyers who put VAT into a landed cost comparison systematically overstate the European option.
Fees and brokerage. Merchandise processing fees, harbour maintenance, customs broker charges, terminal handling, documentation. Small per shipment, material across a year of monthly containers.
The cost of finding a problem late. This is the line nobody budgets. A batch that fails inspection after it has crossed an ocean cannot be replaced in a week. The financial exposure is not the part cost, it is the production line stoppage behind it.
Incoterms, and who actually owns the risk
Incoterms 2020 defines eleven terms, and most zinc casting shipments use four of them. The distinction that matters is not who pays the freight — it is where risk transfers.
FOB (Free On Board). Risk transfers when the goods are on the vessel at the port of shipment. Common in Chinese export practice, and it means you carry the ocean risk. Fine if you have cargo insurance and a forwarder you trust.
CIF (Cost, Insurance and Freight). The supplier arranges and pays freight and minimum insurance to the destination port, but risk still transfers at the port of shipment. Buyers often assume CIF means the supplier is responsible until arrival. It does not.
DAP (Delivered At Place). Risk transfers at your named destination, before import clearance. The supplier carries the ocean risk; you handle duty and clearance. This is often the cleanest split for a buyer without a strong logistics operation.
DDP (Delivered Duty Paid). The supplier handles everything including duty. Convenient, and appropriate for small or one-off shipments. It is a poor default for a repeat programme, because you lose visibility of the duty you are paying, and the supplier becomes importer of record — which affects your ability to claim preferential treatment or dispute a classification.
One practical point that catches people: an Incoterm that names a place, such as DAP Rotterdam, is not the same as DAP your warehouse. Port versus door is a real difference in cost and in who arranges the final leg.
Vietnam, China and origin
Origin is not the same as the shipping port. A part cast in Hanoi and shipped from Shenzhen can still be Vietnamese origin if it was wholly obtained or substantially transformed there, and the documentation has to support that claim.
For the EU, the EU-Vietnam Free Trade Agreement allows preferential duty on Vietnamese-origin goods, subject to the origin rules and the correct proof of origin. For the US, there is no equivalent free trade agreement with Vietnam, but the Section 301 additional duties that apply to many China-origin products are a separate question from the base rate. That combination — same part, same supplier group, two origins, two duty outcomes — is the commercial reason dual-plant sourcing has become so common.
Whether a specific part qualifies is a question for a customs broker with the bill of materials in hand, not for a supplier’s sales team. Ask for the origin declaration and check it covers the actual manufacturing operations, not just the final assembly location.
How to build a landed cost model that holds up
Five columns, per part number: ex-works price, freight and insurance per unit, duty at the code you have verified, fees and brokerage per unit, and a quality contingency. The last column is the one that separates a model from a wish — use your actual rejection and rework history, or a conservative allowance if you have none.
Then run it for both origins. The answer is often not the cheaper ex-works price. A part that is 4 % more expensive from Vietnam can be 8 % cheaper landed if the duty outcome differs, and that arithmetic is invisible in a quotation comparison.
How STK supports the paperwork
We ship from both Xiamen and Hanoi, issue material certificates per lot to EN 10204 3.1, and provide the commercial invoice, packing list and origin documentation that a broker needs to classify the part correctly. The company page describes the two plants, and our article on splitting orders between China and Vietnam covers the commercial logic behind dual-origin sourcing.
What we will not do is tell you which HS code to use. That is your broker’s call, and a supplier who offers a confident classification without seeing your product’s end use is guessing. What we can do is give you the technical description — material, process, function, finished state — that makes the classification straightforward. Contact STK with the part number and destination market.
zinc alloy die-casting factory in China/Vietnam, capable of custom-producing lock parts.
Frequently asked questions
What HS code are zinc die castings?
Most commonly 7907, covering other articles of zinc. Parts that are identifiable components of a specific machine, vehicle or electrical device are often classified in that product’s parts heading instead, which can change the duty rate.
Does the Incoterm change my duty?
Not the rate, but it can change the customs value. Under CIF and DAP terms the freight and insurance are typically included in the value declared, which raises the duty base compared with an FOB purchase where you buy freight separately.
Is import VAT a real cost?
For a VAT-registered business in the EU, no — it is recovered through the VAT return. It is a cash flow item. Treating it as a cost makes European sourcing look more expensive than it is, and it is one of the most common errors in landed cost comparisons.
Can a supplier in China invoice DDP to my door?
They can, and many do. Be aware that the supplier then acts as importer of record, which limits your visibility of the duty paid and your ability to claim preferential origin or challenge a classification later.