Thailand's New 2026 E-Commerce Rules: 5 Platform Behaviors Under the OTCC's Watch

When logistics, payments, algorithms, and fees are no longer just "platform terms of service" but are becoming issues of fairness and market competition.

In an era where marketplaces do more than just connect buyers and sellers, many platforms now control search and ranking, advertising, payments, shipping, promotional participation, and the data that determines which products consumers see first.

When key components of online sales are consolidated under a single system, platforms gain the power to set conditions that directly affect a merchant's costs, sales, and overall competitiveness.

Thailand has introduced new E-Commerce regulations to establish a framework for determining which platform practices may constitute unfair trade, monopolization, or the restriction of competition.

This article explores 5 key behaviors that shops, brands, and service providers in the E-Commerce ecosystem should monitor.

When did the new Thai E-Commerce regulations take effect?

The Office of Trade Competition Commission (OTCC) announcement regarding guidelines for unfair trade practices and actions that constitute monopolization or restriction of competition in multi-sided E-Commerce platforms was published in the Royal Gazette on March 24, 2026, and has been in effect since March 25, 2026.

This announcement does not create new offenses separate from existing laws; rather, it serves as a guideline for interpreting behaviors under the Trade Competition Act B.E. 2560 (2017), ensuring that platform regulation is clearer and better aligned with the nature of the digital market.

Subsequently, on July 6, 2026, the OTCC approved the establishment of a subcommittee specifically tasked with overseeing and deterring anti-competitive behavior on digital platforms. This subcommittee aims to drive measures, monitor conduct, and coordinate with the public sector, private sector, and stakeholders, as announced by the OTCC on July 7, 2026.

This move reflects that platform regulation has moved beyond the guideline-drafting stage and is now entering a phase of active monitoring and enforcement against real-world cases.

What is a Multi-sided Platform?

A multi-sided platform is a space that acts as an intermediary, connecting two or more user groups to facilitate transactions, exchanges, or mutual service reliance.

In the context of E-Commerce, the players in the system include not only the platform, buyers, and sellers, but also:

• Logistics and shipping providers (Carriers)
• Digital advertising providers
• Payment gateway providers
• Technology and other support service providers

The announcement covers platforms that act as intermediaries for the sale of goods and services, including E-Marketplaces, social marketplaces, and other platform models that facilitate transactions via electronic systems.

A key characteristic of this market is the "network effect": a large number of buyers attracts more sellers, and a large number of sellers gives buyers more reasons to use the platform.

At the same time, because platforms hold data, control the matching system between buyers and sellers, and manage product rankings via algorithms, they may possess more power to dictate market direction than traditional commercial intermediaries.

The critical question is not whether platforms can have rules, but whether those rules are reasonable, transparent, and do not unfairly exclude other business operators.

5 Platform Behaviors Merchants and Brands Should Know

The following five behaviors are only a portion of those outlined in the OTCC guidelines. This is not an exhaustive list, and these actions are not automatically considered violations.

Determinations must still be based on facts, economic and business rationale, technology, contractual relationships, and the impact on competition in each individual case.

1. Mandatory Selection of Logistics and Delivery Services

One of the most significant issues is requiring merchants to use only the platform's own delivery service or providers designated by the platform.

The OTCC guidelines address cases where sellers cannot choose other delivery services, including instances where a specific provider is set as the default and sellers cannot easily cancel or change that setting.

Why does this matter to merchants?

Logistics providers affect more than just shipping costs; they also impact:

• Pickup and delivery speed
• Service coverage areas
• Rates of damaged or lost parcels
• Claim conditions
• Cash-on-delivery services
• Store ratings and cancellation rates
• Customer experience

Merchants selling large, fragile, refrigerated, or specialized items may require different logistics services than standard retailers.

If merchants lack the right to choose their providers, their ability to manage costs and control the customer experience may be diminished.

Key issues to watch

Merchants are unable to disable or change system-assigned carriers, there is no clear justification for why certain providers are removed from options, or there is a requirement to use services where the platform or its affiliates have a business interest.

On April 28, 2026, a complaint was filed with the OTCC regarding a platform mandating delivery services. This is a request for a fact-finding investigation, so it should not be concluded that any business operator has committed a violation until a formal ruling is issued.

2. Mandatory Use of Payment, Promotion, or Advertising Services

Platforms can provide convenience to merchants through integrated payment systems, promotions, and advertising services.

However, requiring merchants to use specific services without the ability to refuse or choose other providers can limit options and increase business burdens.

The OTCC guidelines mention behaviors that may require scrutiny, such as:

• Mandating the use of platform-designated payment channels
• Forcing participation in promotional campaigns for extended periods
• Requiring the purchase or use of specific advertising services
• Tying the purchase of one service to access another

Examples cited in the announcement include double-date sales events, payment channels, and the purchase of services from platform-designated media advertisers.

Key distinctions to make

Offering advertising packages, payment systems, or promotions does not automatically constitute unfair business practices.

The real questions are: Can merchants truly opt out? Does declining participation negatively impact visibility or other benefits? And how clearly does the platform disclose costs and terms?

From a brand's perspective, joining campaigns may boost short-term sales. However, if you must continuously rely on discounts, ads, and platform tools just to maintain your existing visibility, your cost of sales may rise faster than revenue, ultimately hurting your long-term margins.

3. Algorithmic visibility reduction

In a physical store, shelf placement directly impacts sales. On digital platforms, placement in search results, recommendation pages, and feeds has the exact same effect.

The difference is that merchants have almost no visibility into the internal workings of these algorithms.

The Trade Competition Commission (OTCC) guidelines address the use of algorithms to block or limit product visibility—known as visibility reduction—without reasonable justification, as well as the use of pricing systems that unfairly affect market prices for goods or services.

This does not mean platforms must disclose their source code or are forbidden from updating their ranking systems, as algorithms remain essential for managing large inventories, detecting fraud, and presenting relevant products to users.

The core issue is whether the criteria for reducing or boosting visibility are fair and backed by sound reasoning.

Warning signs for merchants

• An unusual drop in traffic after declining to join a campaign.
• Products that previously ranked well suddenly disappear without explanation.
• Products with similar attributes receive vastly different rankings.
• A store’s visibility is reduced despite having no history of policy violations.
• Increasing ad spend becomes a de facto requirement to maintain visibility.

However, traffic and product rankings can fluctuate due to many factors, including price, reviews, market demand, content quality, and shipping performance.

Merchants should not jump to conclusions based solely on a dip in sales; instead, they should collect data to compare performance before and after changes to platform terms.

4. Preferential treatment for the platform's own products and services

Some platforms do not act solely as intermediaries; they may also operate their own products, logistics, payment systems, advertising services, or affiliated businesses within the same ecosystem.

This creates a dual role where the platform acts as both the "stadium owner" and a "player on the field."

The OTCC guidelines address "self-preferencing," or favoring one's own products and services over other partners without reasonable justification—such as placing their own items in prominent positions on the homepage without clearly labeling them as advertisements.

The guidelines also cover "data leveraging," which involves using data obtained from partners to gain a competitive advantage for the platform's own businesses, as well as providing superior benefits to their own services compared to those of other partners.

Why is self-preferencing a concern?

The platform has visibility into aggregate data that individual sellers cannot access, such as:

• Trending search terms
• Products with high conversion rates
• Price points acceptable to consumers
• Repurchase rates
• High-demand areas
• Performance of individual promotions

If this data is used to develop the platform's own products or services while the platform also controls product rankings, other partners may be placed at a disadvantage.

However, displaying platform products in prominent positions is not always wrong, especially when clearly labeled as "Sponsored Placement" or advertising space, and when the terms are transparent.

5. Unfair fee collection and changes to terms

The cost of selling on a marketplace today goes beyond just commission fees and may include various charges, such as:

• Commission fees
• Advertising and affiliate ad fees
• Logistics or pickup fees
• Promotion participation fees
• Payment processing fees
• Service fees and other benefits

The OTCC announcement addresses pricing behaviors such as charging excessively high fees, setting rates based on competitors, charging different rates to businesses selling the same goods or services without justification, and imposing unreasonable burdens without reasonable advance notice.

The guidelines also cover changes to commercial terms, adjustments to operational procedures, and delaying payments for goods or services without appropriate prior notice.

High fees do not automatically mean they are unfair.

Fee rates must be considered in conjunction with the services provided by the platform, technological costs, security, transaction management, and market competition conditions.

Key points that shops and brands should consider include:

• Is the cost structure fully disclosed?
• Can the net cost be calculated before participating?
• Is there an advance notice period for fee adjustments?
• Why are similar sellers being charged differently?
• Do new fees come with added services or value?
• Can optional expenses truly be declined?

For brands, it is important not to look only at the commission rate, but to calculate the Total Cost of Platform, which includes all fees, advertising, promotions, discounts, affiliate costs, logistics, and total operating expenses.

Not every platform rule is illegal.

The OTCC announcement does not state that all the aforementioned behaviors are automatically violations.

Actions may not be considered unfair if there is a reasonable economic, business, or technological justification, if they represent standard commercial practice, or if they do not significantly impact overall market competition.

Consideration must also take into account other factors, such as:

• Contractual relationships
• Market nature and structure
• Technological necessity
• Level of impact on partners
• Viable alternatives available to businesses
• Other legal restrictions

Therefore, communication should use terms like "may be subject to," "is a behavior that requires scrutiny," or "is being monitored" rather than concluding that any specific behavior is immediately illegal.

How should shops and brands prepare?

1. Maintain a history of platform terms

Keep records of all versions of Terms and Conditions, Seller Policies, Fee Schedules, and change notifications, including the dates they were announced and when they took effect.

Having only the latest version may not be enough if you need to analyze when changes began and how they have impacted your business.

2. Break down platform costs in detail

Avoid grouping all expenses under a single "Marketplace Fees" category.

You should separate commissions, payment processing, logistics, advertising, affiliate fees, promotions, and merchant-funded discounts to see your true costs and compare them across different periods.

3. Track visibility and performance data consistently

Key data points include:

• Impressions
• Search Ranking
• Product Page Views
• Click-through Rate
• Conversion Rate
• Organic Traffic
• Advertising Spend
• Cost per Order

When anomalies occur, you will be able to analyze whether they are due to demand, product performance, or if they coincide with changes to platform policies.

4. Document limitations and platform communications

If you are unable to change shipping providers, payment methods, or cancel add-on services, keep screenshots, error messages, ticket numbers, and responses from Seller Support.

Evidence with timestamps and a clear sequence of events makes investigations much more effective than relying on intuition alone.

5. Reduce reliance on a single platform

New regulations may help create a fairer framework, but they cannot replace a sound business risk management strategy.

Brands should still diversify their sales channels, develop owned channels, collect first-party data, and build relationships with customers outside of marketplaces so that changes on one platform do not jeopardize the entire business.

How will the new rules change the Thai e-commerce ecosystem?

For platforms, setting terms may now require justifiable reasoning, greater transparency, and consideration of the impact on competition among players within the system.

For shops and brands, these new guidelines provide a clearer framework for challenging potentially unfair terms, but this does not mean that shops will be able to choose every service without limitations.

For logistics, payment, advertising, and technology providers, these guidelines may open up more competitive opportunities, provided platforms cannot block third-party services without reasonable justification.

What to watch for next are the rulings and precedents from actual cases, as these will help clarify the line between standard platform management and practices that may constitute unfair competition.

Frequently Asked Questions About Thai E-Commerce Regulations

When do the Multi-sided Platform regulations take effect?

The announcement was published in the Royal Gazette on March 24, 2026, and has been in effect since March 25, 2026.

Is it immediately illegal to force merchants to use the platform's own delivery service?

It cannot be concluded immediately. Each case requires an assessment of the rationale, necessity, alternatives available to merchants, and the impact on competition. However, mandating a specific carrier without allowing merchants to choose is a behavior identified in the OTCC guidelines.

Can platforms reduce the visibility of products?

Platforms can still manage search and ranking systems, but using algorithms to block or restrict visibility without reasonable justification may be considered a problematic practice.

Are high marketplace fees considered unfair?

High fees alone are not enough to conclude that they are unfair. Factors such as the services provided, costs, the rationale for the rates, differences between partners, and prior notice must all be considered.

Conclusion

As marketplaces become the infrastructure of online commerce, platform power lies not just in connecting buyers and sellers, but in the ability to determine who gets seen, who can reach customers at what cost, and which providers can compete within the system.

The new OTCC regulations are not intended to reject the role of platforms, but rather to strike a balance between system efficiency, innovation, and fair competition within the e-commerce ecosystem.

For merchants and brands, the priority moving forward is to understand true costs, maintain systematic data, monitor changes in terms and conditions, and reduce over-reliance on any single platform.

In the new era of e-commerce, competitiveness may depend not only on who sells the most, but on who best understands the rules, identifies risks, and manages their platform relationships.

Note: This article is intended for information and business impact analysis and does not constitute legal advice or a formal ruling. Determining whether specific behavior constitutes a violation depends on the facts and legal processes of each individual case.

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