Thai Customs Tariff Lookup: How to Find Your Duty Rate

Almost every importer eventually asks the same question: what duty will I pay on this product? The answer is not hidden, but it is easy to find the wrong one. Thailand publishes its full customs tariff, and the Thai Customs Department provides an online search for it. The difficulty is that a duty rate is attached to a tariff line, and the tariff line depends on classifying the product correctly. Type a product name into a search box and you will get a rate quickly, but not necessarily the rate that applies to your goods.

This guide is a practical walk-through of the lookup itself. It explains where the official tariff is, how it is structured, how to search it, how to read a tariff line including the general rate and the free trade agreement columns, what the notes on a line are telling you, and when to stop classifying yourself and ask for a binding ruling. It sits between our explainer on what an HS code is, which covers the concept, and our article on how import duty and VAT are calculated in Thailand, which covers the formula once you have the rate.

Two ground rules apply throughout. First, we do not quote duty rates here, for any product, because rates change by notification and depend on the exact line; always read the current rate from the official source on the day you need it. Second, a tariff lookup is a starting point for a classification decision, not a substitute for one. If your pricing depends on the rate, confirm it with a licensed customs broker or the Customs Department before you commit.

Where is the official Thai customs tariff, and what is it based on?

The official tariff is the schedule to the Customs Tariff Decree B.E. 2530 (1987), as amended, and the Thai Customs Department publishes it in a searchable tariff database reached from its website, customs.go.th; the classification structure follows the ASEAN Harmonised Tariff Nomenclature (AHTN), which is built on the international Harmonized System.

It helps to separate the legal source from the search tool. The legal source is the tariff schedule attached to the Customs Tariff Decree, together with the notifications that set preferential rates under each free trade agreement and other measures. The search tool is the Customs Department's integrated tariff database, which pulls that information together so you can look up a code and see its rates and notes in one place. When the two ever seem to disagree, the legal text and the latest notification prevail, and a broker or the Department can confirm which applies.

The classification structure has layers. The first six digits come from the Harmonized System maintained by the World Customs Organization and are the same in every member country: two digits for the chapter, four for the heading, six for the subheading. ASEAN members then use a common eight-digit level, the AHTN, so Thailand, Malaysia, Vietnam and the other members share the same eight-digit codes for the most part. On the declaration, Thailand adds a short statistical suffix that identifies the statistical unit and finer detail.

The Harmonized System is revised periodically, and AHTN follows those revisions, so codes can move or split between editions. That is one reason an old classification file, or a code copied from an old invoice, can point to a line that no longer exists. Always check that you are using the current edition of the tariff, and note the edition in your records.

What do you need to know about the product before you search?

Before you search, you need the facts that classification depends on: what the product is made of, what it does, what form it is in, its composition by material where relevant, and how it is used, because the tariff is organised by these characteristics rather than by trade names.

A common mistake is to start the search with a commercial name. The tariff does not have a heading for a brand, a marketing term or a supplier's product family name. It has headings for things like articles of plastics, machines performing a particular function, preparations of a particular composition, or textiles of a particular fibre and construction. If you cannot describe the product in those terms, you are not ready to search.

A useful product fact sheet answers a handful of questions. What is it made of, and in what proportions if it is a mix? What does it do, and what is its principal function if it does several things? Is it complete or unfinished, assembled or in parts? Is it put up for retail sale, in bulk, or as a set? Is it powered, and if so how? Is it intended for a specific use, such as medical, agricultural or vehicle use? Technical data sheets, catalogues, safety data sheets and photographs all help, and a broker or customs officer will ask for exactly these if a classification is questioned.

For goods bought from China, the supplier's specification sheet is often the best source, but treat any code printed on it as a hint rather than an answer. Chinese codes are ten digits, EU codes are eight or ten, and only the first six digits are internationally aligned. The six-digit subheading is a sensible starting point for your own search, provided you check it against the product facts rather than assuming it is right.

How do you search the Thai tariff database step by step?

Search from the top down: identify candidate chapters and headings from the product facts, read the section and chapter notes, narrow to the six-digit subheading and then the eight-digit Thai line, and only then read the rate; keyword search is useful for finding candidates, not for choosing the answer.

Step one is to list the candidate chapters. A stainless steel kitchen knife could sit among cutlery, articles of steel or tools, and the chapter notes will tell you which. A plastic toy could sit among toys or plastic articles. Writing down two or three candidates forces you to look at why one wins.

Step two is to read the section and chapter notes for each candidate. Notes define terms and, critically, exclude goods that might seem to fit. Many classification errors happen because someone found a heading whose words looked right but never read the note that sends that product elsewhere.

Step three applies the General Rules for the Interpretation of the Harmonized System, usually called the GRIs. In practice the first rule does most of the work: classification is determined by the terms of the headings and the notes. The later rules deal with incomplete articles, mixtures, sets and goods that could fall into two headings, and they explain why, for example, a set put up for retail sale may be classified by the component that gives it its essential character.

Step four narrows within the chosen heading. Read every subheading at the same level before choosing, including the residual lines labelled other, because the right answer is often the residual one.

Step five is the lookup itself. Enter the eight-digit code into the Customs Department's tariff search, confirm that the description on the line matches your goods, and then read the rates and notes. If the description does not match, go back a step rather than forcing the fit.

Step six is to record what you did: the code, the reasoning, the notes you relied on, the date and the source. That record is what lets you defend the classification later.

How do you read a Thai tariff line?

A Thai tariff line shows the eight-digit code, the description, the unit of quantity, the general rate of duty, and then the preferential rates available under each free trade agreement, plus notes that flag controls or other taxes; read the description first and the rate last.

The description is the part people skip and the part that matters most. Check that every condition in it fits your goods: material, function, whether assembled, whether for retail sale. A line that begins with of a kind used for, or that contains a material threshold, only fits goods that meet that condition.

The unit tells you how quantity must be declared, for example by number, by kilogram or by litre. Even when the rate is a percentage of value, the declaration still needs the quantity in the right unit, and a mismatch can stop an entry.

The general rate, sometimes called the MFN or normal rate, is the rate applied when no preference is claimed. It may be expressed as a percentage of the customs value, as a specific amount per unit, or as a combination in which the higher of two calculations applies. Read the expression carefully, because a specific or combined rate behaves very differently from a simple percentage when prices change.

The preferential columns list the rates under each agreement Thailand applies, such as the ASEAN Trade in Goods Agreement (ATIGA), the ASEAN-China Free Trade Area (ACFTA), the Thailand-Japan agreement and others, as well as regional agreements such as RCEP. Each column is its own legal rate with its own origin rules; we explain how to read them in the next section.

Finally, the notes and links on the line tell you whether the goods face import controls, permit requirements, excise tax or other measures. These do not change the duty rate, but they can decide whether you can import the goods at all, which is why they deserve as much attention as the rate itself.

How do you read the FTA preference columns?

Each preference column is a separate, conditional rate that applies only to goods originating in a partner country under that agreement and only when valid origin evidence is presented; the general rate remains the fallback if the condition is not met.

The first point is that origin is not the same as the country of shipment. Goods shipped from a Chinese port are not automatically Chinese-origin for ACFTA purposes, and goods assembled in Vietnam from imported parts may or may not qualify as Vietnamese origin. Each agreement has rules of origin, often set product by product, that decide whether the goods qualify: wholly obtained, a regional value content threshold, a change in tariff classification, or a specific process. The supplier must be able to meet those rules and document them.

The second point is that the same code can have different preferential rates under different agreements, and sometimes the goods qualify under more than one. Where that happens, the importer can usually choose which agreement to claim, provided the origin evidence matches the agreement claimed. A Form E supports an ACFTA claim, not an RCEP claim, and vice versa. Our article on types of certificate of origin explains which document goes with which agreement, and our guide on how to verify a Form E covers the checks for China-origin goods.

The third point is timing. Preferential rates are set by notification and can change, for example as tariff reduction schedules progress. A rate you saw last year may not be the rate today, and some goods are listed as sensitive or excluded under certain agreements. Read the column on the day you price the goods, and note the date.

Finally, budget on the general rate until the origin evidence is confirmed. If the certificate arrives with an error, or the goods turn out not to qualify, the general rate is what you will pay, and your landed cost should be able to absorb that difference or your contract should say who carries it.

What do the notes and control flags on a tariff line tell you?

Notes on a tariff line flag obligations beyond the duty rate, such as an import permit or licence requirement, standards certification, excise tax, or other measures, and each flag points to an agency or rule you must satisfy before the goods can be cleared.

A duty rate tells you what you pay; a control flag tells you whether you may import at all and on what conditions. Many products that look simple carry controls. Food, cosmetics, medicines and medical devices involve the Thai Food and Drug Administration. Some industrial products fall under mandatory standards administered by the Thai Industrial Standards Institute (TISI). Radio and telecommunications equipment involves the National Broadcasting and Telecommunications Commission (NBTC). Plants, animals and their products involve the agriculture authorities. Our articles on controlled import goods in Thailand and on import permits explain these regimes more fully.

The tariff database can show links between a code and the related permit requirements, and the Customs Department also publishes information on goods that need permission. Use those links as a prompt, then confirm the actual requirement with the relevant agency, because the scope of a control is often narrower or broader than the tariff line. A permit regime may apply only to goods meeting a technical definition, or it may apply across several lines.

Excise tax is another flag to watch. For goods such as vehicles, beverages, petroleum products, batteries and some others, excise is assessed alongside duty at import, and it can be larger than the duty itself. Our article on excise tax on imported goods in Thailand explains how it stacks with duty and VAT.

Anti-dumping and other trade remedy duties are a special case. They usually apply to a combination of product, origin and sometimes exporter, and they may not be visible as a simple rate in the general tariff view. If your product and origin could plausibly be subject to a trade remedy measure, ask your broker to check current measures before you price.

Why can the same product appear to have different duty rates?

The same product can appear to have different rates because it can be described in ways that point to different lines, because rates differ between the general and preferential columns, because a specific or combined rate behaves differently from a percentage, or because the tariff edition or notification has changed.

Classification ambiguity is the most common reason. A smart watch could be argued as a watch, a communication device or a data-processing machine, and each argument leads to a different heading. A plastic storage box with a lid could sit among household articles or packaging. The rate you find depends on which path you followed, which is why the reasoning matters as much as the code.

The second reason is reading the wrong column. Someone who sees a low preferential rate and forgets that it only applies to originating goods with valid evidence will budget too little. Someone who sees the general rate and does not realise the goods qualify for a preference will budget too much and may lose a price advantage.

The third reason is the form of the rate. A specific rate charges an amount per unit, so the effective percentage rises when prices fall. A combined rate applies whichever calculation is higher, so the same line can behave like a percentage at one price and like a specific duty at another. Comparing two products by their headline rate can mislead when one is specific and the other is ad valorem.

The fourth reason is time. Tariff editions change with Harmonized System revisions, and preferential rates move with agreement schedules and new notifications. Third-party websites and old spreadsheets often lag behind. This is why the official source, read on the day, is the only one to rely on, and why secondary sites that list rates, however convenient, should be treated as orientation only.

How do you turn the rate into an estimated duty amount?

Apply the rate to the right base: an ad valorem rate to the customs value, which in Thailand is a CIF-type value converted to baht at the rate Customs prescribes, a specific rate to the declared quantity in the tariff's unit, and a combined rate by calculating both and taking whichever the line specifies.

The customs value is not simply the supplier's invoice price. If the invoice is FOB or EXW, international freight and insurance to the Thai port must be added, and certain other payments such as royalties or assists may belong in the value too. Our article on customs valuation in Thailand covers those adjustments, and the guide on how import duty and VAT are calculated in Thailand walks through the formula with a worked structure.

The duty is only one layer of the import tax bill. VAT is then charged on a base that includes the customs value and the duty, and excise tax and certain other taxes are added into that base for goods that attract them. So a change in the duty rate changes the VAT too. For a full picture of what an import costs, combine the tax calculation with the freight and local charges; our article on Thailand import costs explained and the landed cost guide show how those pieces fit together.

Two cautions help when estimating. First, convert at the exchange rate Customs publishes for the period of import, not at today's bank rate, if you want your estimate to match the declaration. Second, do not round the tariff line to a chapter-level average or a rate seen on a third-party site. If the estimate matters, take the rate from the official line and the base from real documents, then ask your broker to sanity-check it before you quote a selling price.

What mistakes do importers make when looking up tariff rates?

The most common mistakes are trusting the supplier's code, choosing a line from a keyword hit, ignoring section and chapter notes, reading only the preferential column, and using an outdated or third-party rate table.

Trusting the supplier's code is understandable, because the supplier knows the product. But the supplier classifies for its own export declaration under its own national tariff, and its choice is not binding in Thailand. Even at six digits, two customs administrations can reasonably disagree. Use the supplier's code as a lead, then classify independently.

Choosing from a keyword hit is the second trap. Keyword search returns lines whose descriptions contain the word you typed, which may include parts, accessories, materials or unrelated goods. A search for battery will return lines for many kinds of cells, parts and devices. The hit list is a menu of candidates, not a verdict.

Ignoring notes is the third. Section and chapter notes are legally part of the tariff. They decide, for example, whether a part is classified with the machine or on its own, or whether a product counts as a preparation or a raw material. Skipping them is the single most reliable way to reach the wrong heading.

Reading only the preferential column is the fourth, and it is often linked to optimism about origin. The fifth is relying on a rate table from a third-party site, a forum or a previous shipment without checking the current edition and notifications.

There is a sixth, quieter mistake: not writing anything down. If you classify a product once and nobody records why, the next person to import it will repeat the work and may reach a different answer. A one-page classification record per product prevents that, and it is exactly what an auditor will ask for in a post-clearance audit.

When should you stop self-classifying and get an advance ruling?

Stop self-classifying and seek an advance ruling from the Thai Customs Department when two headings remain plausible after reading the notes, the rate difference matters to your pricing or contracts, and you will import the product repeatedly; for one-off or low-stakes doubts, a broker's opinion is usually enough.

An advance ruling is a written decision by Customs on how a specific product will be classified, issued before import on the basis of the product information you submit. Its value is certainty: once you hold a ruling for a product, you and your broker can declare on that basis, and disputes at the border become much less likely as long as the goods match the description in the ruling. Our article on customs advance rulings for HS codes in Thailand explains the application, the information usually required and the limits of a ruling.

The decision is a cost-benefit judgement. Preparing an application takes effort: a detailed description, technical documents, sometimes samples, and a reasoned proposal of the classification. For a single shipment of low-value goods, that effort may not pay off, and a licensed broker's view, recorded in your classification file, is a sensible level of diligence. For a product line you will import every month, where one heading carries a materially different rate or a permit requirement and the other does not, a ruling protects your margins and your compliance position for as long as it remains valid.

Rulings have limits. They apply to the product described, so a change in specification can take the goods outside the ruling, and they can be affected by later changes in the tariff. Keep a copy with your classification file, check it when the product changes, and make sure your broker uses it.

A forwarder such as Thai Global Freight (TGF) can coordinate the shipment around that process, booking cargo and lining up documents for the customs handoff, while the ruling itself is a matter between the importer, its broker and the Customs Department.

How should you record a classification so it holds up later?

Keep a one-page classification record for each product that states the eight-digit code, the product facts it rests on, the notes and interpretation rules applied, any ruling or broker opinion, the tariff edition and date checked, and any permit or excise flags.

This record does three jobs. It makes repeat imports faster, because the next shipment becomes a check that the product has not changed rather than a fresh classification. It keeps your declarations consistent, which matters because inconsistent codes for the same product across shipments are a red flag for risk systems and auditors. And it gives you a defence if Customs later questions the code, because you can show a reasoned decision made in good faith.

A practical template has a handful of fields:

• Product name, internal SKU and supplier part number.
• Product facts: material and composition, function, form, how it is put up, intended use.
• Candidate headings considered and why each was accepted or rejected.
• The section and chapter notes and interpretation rules relied on.
• Final eight-digit code, the general rate and the preferential columns relevant to your origins, read on a stated date.
• Control flags: permits, standards, excise, any trade remedy check.
• Supporting evidence: data sheets, photos, broker opinion, advance ruling reference.
• Review trigger: specification change, new supplier, tariff edition change.

Share the record with your broker so that the code on the declaration matches the code in your file, and review the file whenever the product or the tariff changes. Our article on the Thailand import declaration explains how that code then flows into the entry, and the first-time importer checklist places classification within the wider preparation for an import.