Customs, Import–Export & Tariff Disputes in Thailand

Tariff classification disputes: the same goods, read two ways

The same physical product can fall under more than one heading depending on function, principal component, or the last stage of manufacture, and headings carry very different duty rates. Many importers simply adopt the code their overseas supplier suggests without testing it against Thailand's own interpretive rules, so when an officer later disagrees the result is a retroactive reassessment plus surcharges.

Where a disagreement arises, we typically start by seeking an advance ruling from Customs for a new product line before it is actually imported, cutting the risk of a later challenge. Where goods have already cleared and a question has been raised, we assemble technical data sheets, catalogues and classification opinions from trading partners on the same Harmonized System to support the code the importer has been using.

If a dispute is not resolved at the release-checking level, the next forum is the tariff appeal committee, which weighs technical documentation more heavily than pure legal argument. We therefore invest as much in a credible product-expert report as in the legal submission, since the committee tends to decide on the physical characteristics and actual use of the goods.

Customs valuation and royalty or licence-fee add-backs

The customs value used to compute duty is not always simply the invoice figure. Customs may adjust it upward for items connected to the sale — freight to the border, insurance, buying commissions — and the issue that recurs most in multinational structures is royalty or licence fees a foreign parent charges its Thai subsidiary. Where the overseas seller would not have released the goods at all without that fee being paid, Customs folds it into the dutiable base.

In practice the royalty agreement is usually drafted by the parent's overseas legal team with no thought given to Thai customs consequences. We read the licence agreement, the sale-of-goods contract and the transfer-pricing policy together to see whether the fee is genuinely tied to the imported goods or to a separate right — such as the local retail use of a trademark — that need not be added back.

When a post-clearance audit finds that a royalty should have been added back but was not declared, the result is a retroactive assessment with surcharge applied to every shipment across the audit period, sometimes stretching back years. We advise clients with cross-border royalty structures to review this exposure periodically rather than waiting for an officer to open the question.

Post-clearance audits and seizure of goods

Clearance at the port is not the end of liability. Customs retains the right to audit an importer's books and records for a defined look-back period, and such audits typically start with a sample of import entries and supporting documents, then expand across the whole period if the sample reveals discrepancies. Businesses should therefore keep import and export paperwork complete and ready for immediate review on request.

Where officers suspect false declaration, duty evasion, or a breach of licence conditions, they may seize or detain the goods and documents at once, without waiting for a court ruling. This hits cash flow hard because detained stock sitting at the port or a bonded warehouse cannot be delivered to customers. We move to negotiate a release against security from day one, rather than letting the matter drag on and damage the client's own sales contracts.

Settling a penalty with Customs is a genuine option in many cases, particularly where the breach stemmed from a good-faith misunderstanding rather than intent to evade. A settlement usually secures faster release of the goods and closes the matter without the much longer criminal track. We assess up front whether a client's facts fit a negotiated settlement or warrant a full contest, since the two routes carry very different costs and timelines.

Duty drawback under Section 19 bis and free-zone privileges

Manufacturers importing raw materials to produce for export can reclaim import duty under Section 19 bis of the Customs Act, provided they can prove the imported material was actually consumed in producing the exported goods, according to a production formula pre-approved by Customs. A common failure point is that the factory's actual formula drifts as technology changes while the formula on file with Customs is never updated, so refund claims are rejected for a mismatch in the figures.

We help clients rebuild and keep formulas current with what actually happens on the line, alongside a tracing system from raw-material entry through to the exported finished good, so questions on a refund claim can be answered on the spot during audit. There are also alternative structures for export manufacturers, such as duty exemption under Section 29, or operating from a free zone or bonded warehouse instead of paying duty first and reclaiming it later, which eases the upfront cash burden.

Choosing a free zone or bonded warehouse must be weighed against the administrative cost of operating inside it — separate stock ledgers, advance notice for moving goods in and out of the zone, and annual renewal conditions for the operating licence itself. We set out both the tax saving and the operational cost side by side before a client commits to moving production into a free zone.

Certificates of origin and FTA preferential rates

Claiming a reduced or zero rate under a free trade agreement requires a certificate of origin issued correctly under that agreement's own rules of origin, and the rules differ across agreements — some use a change-in-tariff-classification test, others a regional value-content threshold. An exporter using the wrong certificate format or miscalculating the value content risks the destination country clawing back the preference and charging the full duty rate retroactively.

Conversely, a Thai importer relying on a certificate of origin issued by a trading partner still bears the risk if Customs later finds the goods do not meet the origin criteria in substance, even where the importer acted in good faith on the certificate received, because it is the importer who makes the declaration to Customs. We advise clients to keep supporting origin documentation from suppliers on hand as a backup set rather than relying on the certificate alone.

Where an origin dispute arises, verification usually has to be coordinated with the issuing authority in the country of export, which takes longer than a purely domestic matter. We therefore keep two contingencies running at once: seeking deferral of duty payment while the origin verification is pending, and pre-calculating the full-rate duty exposure in case the verification comes back unfavourable, so the business is never blindsided by a sudden figure.

Appeals to the committee and litigation at the Tax Court

Where a Customs audit or reassessment goes against the operator, the right of appeal to the appeal committee must be exercised within the statutory period counted from receipt of the decision. This step is a mandatory precondition to bringing the matter to the Central Tax Court in almost every case, and skipping straight to court carries a high risk of the claim being refused for failure to exhaust the internal remedy.

At the committee stage the weight of the argument tends to sit with technical and accounting documents rather than legal interpretation alone. We build the appeal file to include legal analysis, a duty reconciliation schedule, and a product or accounting expert opinion as each case requires, so the committee can see the full picture in a single review.

If the appeal decision still goes against the operator, the final step is filing to revoke the decision at the Central Tax Court, which hears customs matters alongside other tax cases. A parallel decision at filing is whether to seek suspension of the remaining duty payment while the case proceeds, since surcharges continue to run in the meantime. We calculate the cost of posted security against the accruing surcharge so the client can decide with the numbers in hand.

Building internal compliance before Customs comes calling

Businesses that import and export routinely gain far more from building an internal review system upfront than from firefighting once an audit lands. At minimum that system should include reviewing the tariff classification of any new product line before its first import, periodically reconciling the declared price structure against the actual sale contract, and keeping full origin-supporting documentation ready for inspection at any time.

We design a checklist tailored to each business covering the classification, valuation and origin risk points, with a named internal owner for each step, so customs knowledge does not sit with a single employee and vanish when that person leaves. Training the procurement and logistics teams to weigh the customs impact at the contract-negotiation stage prevents far more problems than trying to fix them after goods have already cleared.

For businesses with a mixed structure — importing raw materials both for export production and for domestic sale — we recommend keeping the two tracing systems clearly separated from the outset, since mixing them is the single most common cause we see of a Section 19 bis refund claim being rejected later.

When to act, and when waiting is fine

• Before importing a new product line that has never cleared before

  Seek an advance classification ruling before the first shipment; it costs far less than unwinding a retroactive assessment later.

• Where the business pays royalties to an overseas parent

  Review the licence agreement against customs rules before an officer raises it during a post-clearance audit.

• When goods are seized or detained at the port and delivery deadlines are at risk

  Negotiate release against security from day one; do not wait until it breaches the sale contract with the end customer.

• No need for litigation if the issue is a documentary gap fixable at the appeal stage

  Complete the supporting file and close the matter at the appeal-committee stage, saving both time and cost compared with litigation.