On March 24, 2026, the Trade Competition Commission of Thailand (TCCT) published its long-anticipated Guidelines on Multi-Sided Platforms and E-Commerce Businesses in the Government Gazette, following the conclusion of a public hearing conducted last year. The guidelines entered into force on March 25, 2026, and significantly expand the application of Thai competition law to digital platform ecosystems.

These rules introduce targeted restrictions on platform conduct, such as price-ranking algorithms and tying and bunding, that leverages network effects, and will have far-reaching implications across Thailand’s digital economy—affecting not only platform operators but also platform participants, including sellers, logistics providers, advertisers, and payment service providers operating on or alongside such platforms.

The guidelines clarify how existing prohibitions under the Trade Competition Act B.E. 2560 (2017) (TCA)—including abuse of market dominance, cartel conduct, and unfair trade practices—apply in the context of platform-based business models. While many provisions reflect earlier draft guidelines, the final version delivers more precise definitions and clearer enforcement parameters, increasing regulatory certainty while also raising compliance expectations.

Applicability

The guidelines introduce core definitions that determine their coverage:

• Multi-sided platform: A platform that acts as an intermediary connecting two or more groups of users, enabling them to have direct interaction in order to exchange or rely on services from one another. Examples include digital platforms for trading goods or services (e-commerce), as defined below.
• Digital platform for trading goods or services (e-commerce): A platform that acts as an intermediary connecting the distribution, purchase, sale, or exchange of goods or services. This includes operations carried out to facilitate transactions or interactions between business operators through an electronic transaction system, regardless of whether a service fee is charged.
• Operator of a digital platform business for trading goods or services: A provider of digital platform services for trading goods or services, as described above, operating by receiving purchase orders for goods or services transacted via electronic systems, whether in the form of an electronic marketplace, social media marketplace, or any other format that connects purchase orders for business operators’ goods or services through an electronic system.

The scope of the guidelines is intentionally broad and extends to sellers, carriers, digital media advertisers, payment channels, and platform operators that use algorithms to rank, match, or display goods or services.

Restriction of Practices

The guidelines do not adopt a per se illegality standard but rather apply a rule-of-reason principle to various price-related practices and other conduct, as described below. The conduct may still be acceptable—or in other words, not considered unfair or unreasonable—if it meets specific criteria for exemption, such as being supported by sound economic, business, or technological reasoning, or aligning with established trade practices and market customs intended to enhance or maintain competition.

The conduct must not significantly harm overall market competition, nor should it result in excessive restriction, distortion, or the imposition of an unfair burden on other business operators. Regulatory assessment may also take into account external factors such as contractual relationships and other legal limitations.

Price-Related Practices Under Scrutiny

The price-related practices now within the TCCT’s enforcement focus include:

• Below-cost pricing: Setting prices for goods or services below their total average cost, including charging fees, expenses, or other benefits at a rate lower than the average total cost.
• Predatory pricing: Charging fees, expenses, or other benefits at a rate lower than the average variable cost from sellers, carriers, digital media advertisers, and payment channels with the objective of foreclosing competitors. Predatory pricing requires demonstrable or foreseeable recoupment to offset previous losses and maximize long-term profits.
• Rate parity clauses: Requiring sellers to match the platform’s prices across other channels or preventing sellers from offering lower prices elsewhere.
• Resale price maintenance: Dictating the resale price at which sellers offer goods or services.
• Refusal to deal: Refusing to deal with sellers who do not comply with specified pricing requirements.
• Excessive or unreasonable pricing: Charging commissions, advertising fees, logistics fees, promotional fees, or payment-processing fees that are not reasonably justified or proportionate.
• Price discrimination: Charging different prices or fees to similarly situated sellers or service providers.
• Price-ranking algorithms: Using algorithms that systematically prioritize or deprioritize goods or services based on pricing in a manner that harms fair competition.

Nonprice Conduct Under Scrutiny

The guidelines also impose extensive restrictions on nonprice conduct common in platform operations, including:

• Visibility reductions: Lowering the search ranking or display prominence of sellers’ products.
• Self-preferencing: Favoring the platform’s own goods or services over third-party offerings.
• Exclusionary conduct toward carriers: Refusing to allow goods delivery by seller-chosen carriers or setting default carrier assignments that prevent sellers from selecting alternative logistics providers.
• Mandatory sales promotions: Compelling participation in sales promotion activities for an extended and continuous period, such as recurring monthly “double-date” sales promotions.
• Mandatory payment channels: Requiring the use of payment services provided or designated exclusively by the platform.
• Coercion to purchase: Requiring the purchase or use of any services without reasonable justification—such as utilizing a designated media advertiser.
• Exclusive dealing arrangements: Requiring sellers to list or sell goods exclusively through the platform, or prohibiting sellers from offering products on competing platforms.
• Refusal to deal: Banning seller accounts, delisting products, or refusing to transact with sellers.
• Restriction of alternatives: Forcing sellers to purchase unrelated services or agree to unrelated contract terms as a condition of platform access (tying and bundling), anticompetitive use of third-party data, limiting seller choice and delisting carriers
• Discrimination: Ranking discrimination and quantity discrimination against certain carriers.
• Abusive data leveraging: Using competitively sensitive data obtained from third-party sellers to benefit the platform’s own competing products.
• Self-preferencing through data use: Exploiting proprietary data to advantage the platform’s offerings.
• Collusive conduct: Platforms colluding with one another on competitive terms, including keyword-bidding collusion.

Next Steps

The TCCT has enforcement authority to investigate, issue cease-and-desist orders, and impose penalties for violations. Platform operators and participants should review their commercial terms, algorithms, pricing policies, and contractual arrangements to ensure compliance with the new restrictions. Companies should also consider conducting internal compliance assessments and seeking legal guidance to address any potentially problematic practices before enforcement actions commence.