Rules around a Thai PCB order: factory permits, environment and trade

A printed circuit board ordered from Thailand passes through two sets of rules. The first governs the plant: its factory permission, what it may discharge, and whether it sits in an industrial estate. The second follows the board after it ships: its origin, the duty it pays on arrival, and the chemical and contract rules that US and EU buyers apply. Every one of the 39 plants in the MPBxChange register works inside this framework. This article summarises both sides from official texts as they stood on 24 September 2026. It is general information, not legal advice.

Part 1: making boards in Thailand

The Factory Act and its three classes

The Factory Act B.E. 2535 (1992) lets the Minister of Industry sort factories into three classes according to how much control they need. A Class 1 factory may start operating at once, a Class 2 factory must notify the authorities first, and a Class 3 factory needs a licence before it is set up.^[1] The same Act lets the Minister set, by ministerial regulation, standards and methods for controlling the release of waste and pollution from factory operations.^[1]

An amendment in 2019 redefined a factory as a building, place or vehicle that uses machinery of 50 horsepower or more in total, or 50 or more workers, in a type of business listed by ministerial regulation. The same amendment ended the requirement to renew factory operating licences.^[2]

Which class and category a PCB plant falls into is set by the ministerial regulation that lists factory types. We could not open that regulation from an official source, so this article does not state a category number. A buyer can ask the plant for its factory licence or IEAT permit and read the activity listed there.

Plants inside industrial estates

A plant inside an industrial estate also works under the Industrial Estate Authority of Thailand (IEAT) Act B.E. 2522 (1979). Anyone operating a business in an estate needs a permit from the IEAT Governor. Where other laws require a licence, including the laws on factories, building control and public health, the Act gives that power to the Governor, and the Governor's permission counts as the other agency's.^[3] The Act also allows an estate operator to be permitted to own land beyond limits set in other laws, and to bring in foreign skilled workers, specialists and their families beyond normal immigration limits, to work in positions the IEAT Board approves.^[3]

Our reading of section 42 is that an estate tenant deals mainly with the IEAT for permissions a plant outside an estate seeks from several agencies.

Wastewater: the copper line

PCB fabrication etches and plates copper, so the effluent limits for metals are the numbers that matter most. Two official sets of limits apply, depending on where the water goes. Water released to the environment falls under Notification No. 3 (B.E. 2539, 1996) of the Ministry of Science, Technology and Environment, issued under the national environmental quality law for factories and estates.^[4] Water sent into an estate's central treatment plant falls under IEAT Notification No. 76/2560 (2017).^[5]

The first column comes from the 1996 notification^[4] and the second from the IEAT notification.^[5]

The estate allows a higher organic load, which its central plant then treats, but the metal limits are identical. In practice a PCB line's copper has to be treated inside the plant either way. The IEAT notification says so directly: an operator whose water does not meet the limits must build its own pre-treatment system before discharging to the central sewer.^[5] It also allows different limits where the estate's approved environmental impact assessment sets them.^[5] The Factory Act also lets the Ministry of Industry set discharge standards for factories;^[1] We could not open the Ministry's current notification, so the table leaves it out.

Industrial waste

Inside estates, IEAT Notification No. 79/2554 (2011) divides industrial waste into hazardous and non-hazardous waste, requires operators to follow the Ministry of Industry's rules on disposal, and requires an annual report to the estate office by 1 March of the following year.^[6] Spent etchant, plating sludge and drilling dust are routine PCB wastes. Whether each one counts as hazardous is decided under the Ministry of Industry's rules, which the IEAT notification points to and which We could not open.

Is an environmental impact assessment needed?

The current list of projects that need a full environmental impact assessment (EIA) is a 2023 notification of the Ministry of Natural Resources and Environment, published in the Royal Gazette in January 2024.^[7] It lists industrial estates, industrial zones under the factory law and industrial land allocation at every size, along with heavy process industries such as petrochemicals, chlor-alkali, cement, pulp, steel and non-ferrous smelting at set capacities.^[7] we read the list and found no entry for printed circuit board or electronics manufacture. On that reading, a PCB plant does not need an EIA because of its type alone, but a plant inside an estate operates under the estate's approved EIA, which can set its discharge limits.^[5]

BOI promotion in brief

The Board of Investment's current guide lists board-making activities under heading 4.2.4, each with a condition and an incentive group.^[8]

Printed circuit board assembly is a separate activity under heading 4.2.5.^[8] The recurring condition is that a board maker must run its own circuit trace process. What each group receives, and any later changes, are on the BOI website. BOI reports more than 331 billion baht of investment in PCBs and electronic components across 224 projects since 2023.^[9]

Part 2: buying boards made in Thailand

What makes a board "made in Thailand"

Two questions differ: the ordinary country of origin that customs uses for marking and most extra duties, and preferential origin under a trade agreement, which decides whether a lower tariff applies.

For the United States, the country of origin is where the article was manufactured, and work done in another country must bring about a "substantial transformation" to move the origin there.^[10] US Customs and Border Protection (CBP) decides this case by case. In an April 2026 ruling, CBP found that surface-mount and through-hole assembly of components onto bare boards in the United States, followed by programming, was a substantial transformation: the product moves from a bare board to a functioning assembly.^[11] In May 2026 CBP confirmed that the same test decides origin for Section 301 duties, and held that a headset's origin was Vietnam, where its circuit board assemblies were built by surface-mount assembly.^[12] For assembled boards, the place of assembly carries great weight. For a bare board etched in Thailand from imported laminate, we found no published CBP ruling in our searches, so that answer is less settled; an importer can request a binding ruling, as the requester did in the April case.^[11]

Printed circuits sit under US tariff heading 8534.00.00, which carries a general duty rate of free.^[13] The extra duties described below are therefore most of the US duty on a Thai board.

For trade inside ASEAN, the ASEAN Trade in Goods Agreement (ATIGA) treats a good as originating if its regional value content is at least 40 percent or if all non-originating materials change tariff heading at the four-digit level, with the exporter choosing the test; product-specific rules can replace these.^[14] A separate clause deems information technology products listed in its Annex 4 to originate where they are assembled from materials covered by the same annex.^[14] The Annex 4 list published by Thai Customs includes single-sided, double-sided and multilayer printed circuits under heading 8534.^[15] Each of Thailand's other agreements has its own rules, so check the one for the destination market.

US tariffs and transshipment, as of 24 September 2026

The legal basis for extra US duties on Thai goods changed twice in 2026.

After the Supreme Court decision, Executive Order 14389 ended the duties imposed under the International Emergency Economic Powers Act (IEEPA), including those under the April 2025 reciprocal tariff order as amended, and stated that it did not affect section 232 or section 301 duties.^[20] Our reading of the two orders together is that the 40 percent transshipment rate, set under the same IEEPA orders, ended with them. In July 2026 CBP described the process it was building for court-ordered refunds of IEEPA duties.^[17]

The section 301 duty rests on a USTR finding that Thailand, among other economies, does not impose and effectively enforce a ban on imports made with forced labour.^[19] The exempt products are listed in the notice's annexes, which appear as images in the Federal Register text we read, so check the board's tariff code against them directly.

A June 2026 executive order told US agencies to prioritise cases of misclassification, undervaluation and illegal transshipment, including investigations under the Enforce and Protect Act.^[21] In September 2026 CBP opened an advance notice of proposed rulemaking on wider supply chain disclosures aimed at goods illegally transshipped, with comments due by 1 December 2026.^[22] Thailand has run its own checks since November 2019, when it set up a watchlist of high-risk products bound for the US and required extra origin documents; a peer-reviewed study found the watchlist did not reduce Thai exports to the US or imports from China.^[23] The origin a buyer declares should match where lamination, drilling, plating and assembly actually took place.

EU: RoHS and REACH

The RoHS Directive (2011/65/EU) requires that electrical and electronic equipment placed on the EU market, including cables and spare parts, does not contain the restricted substances in its Annex II.^[24] The limits apply by weight in each homogeneous material: 0.1 percent for lead, mercury, hexavalent chromium, PBB, PBDE and four phthalates (DEHP, BBP, DBP, DIBP), and 0.01 percent for cadmium.^[25] The duty to draw up the EU declaration of conformity and affix the CE marking falls on the manufacturer of the finished product.^[24] A bare board is usually a component, not finished equipment, so the EU manufacturer typically asks the Thai plant for material data on each layer: laminate, solder mask and surface finish.

Under REACH (Regulation 1907/2006), any supplier of an article containing a Candidate List substance above 0.1 percent by weight must give the recipient enough information for safe use, including at least the substance's name, and must answer a consumer's request within 45 days.^[26] Producers and importers must also notify the European Chemicals Agency when such a substance exceeds one tonne a year in their articles.^[26]

Conflict minerals

The EU Conflict Minerals Regulation (2017/821) places due diligence duties on EU importers of tin, tantalum, tungsten and gold as ores, concentrates or metals above set volume thresholds, from 1 January 2021.^[27] An importer of finished boards is not directly covered on that wording. In the United States, the SEC rule applies to companies that file reports with the SEC when these minerals are necessary to the functionality or production of a product they make or contract to make, with an annual Form SD due by 31 May.^[28] Tin in solder and gold in surface finishes mean that customers subject to these rules will ask a Thai board maker where its metals came from.

Drawings, NDAs and electronic signatures

Gerber files and fabrication drawings are protected in Thailand as trade secrets only if the information is not public, has commercial value because it is secret, and its controller has taken appropriate measures to keep it secret.^[29] The Trade Secrets Act B.E. 2545 (2002) treats breach of contract as a dishonest trade practice, and lets the owner seek an injunction and damages.^[29] It allows reverse engineering of a product obtained in good faith, but not where the person expressly agreed otherwise with the owner or seller.^[29] An NDA that forbids reverse engineering, plus confidentiality markings and need-to-know access, is therefore more than a formality. The Department of Intellectual Property's English text is an unofficial translation; the Thai text governs.^[29]

Signing that NDA electronically is recognised. Under the Electronic Transactions Act B.E. 2544 (2001), a message may not be denied legal effect only because it is in electronic form. Where a signature is required, an electronic method counts if it identifies the signer and shows the signer's intention and is reliable for the purpose or proven by other evidence. The Act also lists the features of a reliable electronic signature.^[30]

How this was researched

Researched on 24 September 2026 from official texts: Thai Acts and notifications in Thai from government sites, English translations published by Thai agencies, EU legislation from the EU Publications Office, US orders, notices and CBP rulings from govinfo.gov and CBP's rulings database, and one peer-reviewed study. We could not open an official copy of the Ministry of Industry's factory classification, its effluent and waste notifications, or the Hazardous Substance Act B.E. 2535, so the article does not describe them. Only the plant count comes from the MPBxChange register of PCB plants researched in Thailand.

This is general information current at 24 September 2026, not legal advice; check the current official text and take professional advice for any specific case.