Tariffs and US Stone Imports — How to Read the Duty Stack Before You Quote

The quote that was wrong before the stone moved

A pattern we hear repeatedly from US importers over the last two years: a container is quoted, approved and booked on a landed-cost model built when the order was placed, and by the time it clears customs the duty line looks nothing like the spreadsheet. Nobody misquoted the stone. The duty stack moved underneath it.

Tariff policy has become one of the most volatile inputs in the stone trade, and it is the input most buyers model least carefully. This is not a guide to any particular rate — rates change, and several have been through revision and litigation. It is a guide to the structure, because the structure is what your process has to survive.

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The duty stack, layer by layer

What US Customs collects on an imported stone shipment is rarely a single rate. Think of it as a stack, and price every layer separately:

• 1. The base HTS rate. The Harmonized Tariff Schedule rate for the classification, at the column applicable to the country of origin. For much raw and simply worked stone this rate is low or free — which is exactly why importers who only look here get surprised later.
• 2. Trade-remedy actions. Section 301 duties on goods of Chinese origin apply to a list of classifications, several of which cover worked stone and stone articles. Section 232 duties on steel and aluminium, and their expanding derivative-product lists, do not hit the stone itself — but they can hit the anchors, brackets and ventilated-facade substructure shipped alongside it.
• 3. Antidumping and countervailing duty orders. This is the layer most people forget. Quartz surface products have been subject to AD/CVD orders covering material from China and, separately, from India and Turkey. AD/CVD rates are producer-specific, can run to triple digits, are assessed retrospectively at administrative review, and are not something a customs broker can negotiate away. If you import engineered quartz, checking the order scope and the specific producer rate is not optional.
• 4. Country-specific measures. Since 2025 the US has layered additional country-level tariffs on top of the schedule through executive action, with rates differing sharply between producing countries and revised more than once. Some have been contested in court. Treat whatever number you have today as perishable.
• 5. Fees. Merchandise processing and harbour maintenance fees are small individually and easy to omit from a model that is already wrong by thirty percent.

Classification is where the money is

Most disputed duty on stone traces back to classification, not to policy. The broad divisions matter: crude or roughly trimmed blocks and simply cut slabs sit in Chapter 25, worked monumental and building stone sits in heading 6802, and agglomerated or reconstituted stone sits in 6810. The difference between simply cut and further worked — calibrated, polished, edge-profiled — can move a shipment between headings, and with it the entire remedy exposure attached to that heading.

Two habits protect you. First, put the claimed HTS code on the proforma invoice and agree it with your supplier before production, not at the port. Second, where there is genuine ambiguity and the volume justifies it, request a binding ruling from CBP rather than guessing — and check the published rulings database first, because it often answers the question for free.

Country of origin is not the country on the invoice

Origin for duty purposes follows where the goods were produced or last substantially transformed — not where your seller is registered, and not where the container was loaded. For natural stone this usually means the quarry country, and cutting or polishing in a third country does not necessarily change it. Ask for quarry documentation as a matter of routine, and be sceptical of any offer whose main selling point is a convenient origin. Misdeclared origin is the importer's liability, and it is treated seriously.

Who actually pays — and what your contract says about it

The importer of record owes the duty, full stop. So the commercial question is what your Incoterms and your contract do when the rate moves between order and arrival:

• On FOB or CIF terms the buyer carries the duty risk entirely.
• On DDP the seller does — which is why many exporters stopped quoting DDP into the US.
• A duty-change clause is now standard practice in well-drafted contracts: it names the rates assumed at the time of the order and specifies what happens — renegotiate, share, or cancel without penalty — if they change before entry.

If your purchase orders do not address this, the outcome of a tariff change is decided by whoever has more leverage when the argument happens.

Five changes worth making this quarter

• Build a landed-cost model with duty as its own line, broken into the layers above, rather than a single percentage bolted onto FOB.
• Record the HTS code, claimed origin and any applicable AD/CVD case number on every order document.
• For multi-tier transactions with a middleman, ask your broker whether first-sale valuation is available to you — where it applies and is properly documented, it is one of the few legitimate levers left.
• Add a duty-change clause to your standard terms.
• Keep entry records for five years, filed where you can actually find them. Post-entry reviews arrive long after everyone has forgotten the shipment.

What this looks like from the export side

If you quarry or fabricate outside the US, three things make you easier to buy from in a high-tariff environment: flexibility on Incoterms so the buyer can control the customs entry, complete and honest origin documentation supplied without being chased, and market diversification so that one destination's policy swing does not decide your year. Exporters who spent the last two years building Gulf, EU and Southeast Asian channels have had a materially calmer time than those who did not.

The durable lesson

Every specific rate in this article will eventually be out of date. The process will not be. Importers who classify carefully, document origin, model duty in layers and contract for change will absorb the next policy shift as an inconvenience. Everyone else will absorb it as a loss. On LithoPrime, vendor profiles carry the country and quarry information you need to start that analysis before you even request a quote.

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Further reading

• USITC Harmonized Tariff Schedule — the authoritative source for current classifications and rates.
• CBP — trade remedies and the CROSS ruling database.
• ITA ACCESS — antidumping and countervailing duty orders, scope rulings and producer-specific rates.
• Federal Register — where changes are published before they reach your broker's inbox.

Tariff rates, remedy scopes and country measures change frequently, and some remain subject to litigation. Nothing here is legal or customs advice — verify current rates against the HTS and the relevant agency notices, and work with a licensed customs broker on live entries.