If you’ve ever sent a message to a buyer that never arrived, or received a warning from Mercado Libre without understanding why, chances are you triggered the banned words filter. This guide explains how that filter works, which categories of words it blocks, and — most importantly — how to rewrite your messages to communicate the same thing without any risk.
Why Mercado Libre Filters Certain Words
Mercado Libre processes millions of messages between sellers and buyers every day. To protect the integrity of its ecosystem and enforce its usage policies, the platform applies automatic filters that detect text patterns associated with risky behavior.
The primary goal is to prevent off-platform transactions: sellers and buyers closing deals outside the platform (which would eliminate buyer protection and Mercado Libre’s commission). Secondarily, the filters also block language that could be used to pressure buyers, share banking details directly, or avoid disputes.
Important: the filters do not distinguish intent. If you use a blocked word in a completely legitimate context — for example, writing “feel free to ask me anything” — the system detects it anyway. There’s no automatic appeal based on context.
According to Mercado Libre’s messaging policy, sellers are responsible for the content they send, and repeated violations can lead to account suspensions.
The 6 Categories of Blocked Words
The Mercado Libre filter is not a single arbitrary list. It responds to categories with their own logic. Below are the most relevant categories with concrete examples:
Category 1 — Language Redirecting to External Channels
Any reference to contact methods outside of Mercado Libre is the most aggressively filtered category. The system interprets that you’re trying to take the conversation off the platform.
| Word / example phrase | Why it’s blocked | What happens if you use it |
|---|---|---|
| WhatsApp, Telegram | External channels | Message held |
| Instagram, Facebook | External social networks | Message held |
| Email, e-mail | External channel | Message held |
| Phone, cell + number | Off-platform contact | Message held |
| ”message me at…” | Explicit redirection | Warning + held |
Category 2 — Words Simulating Urgency or Commercial Pressure
Mercado Libre detects phrases that could be used to pressure buyers into deciding quickly or not opening disputes.
Blocked or high-alert examples: “don’t open a claim”, “before the deadline expires”, “if you don’t respond you lose the benefit”. The phrase “don’t open a claim” is explicitly documented in filters used by the platform’s automatic messaging tools.
Category 3 — Delivery and Logistics Terms with Conflicting Load
Words like shipped, dispatched, delivery, delivered, courier, and phrases like “has been shipped” can trigger alerts when used in certain contexts, especially if they appear alongside Category 2 words.
The system is more permissive with these terms in the context of standard post-sale messages (dispatch notifications), but stricter when they appear next to pressure-related words.
Category 4 — Personal and Banking Data
Including bank account numbers, routing numbers, card numbers, or any direct payment data in a message is strictly blocked. This also applies to indirect references like “I’ll share the details here.”
Category 5 — Thank-Yous and Premature Closing Language
Phrases like “thank you for your purchase”, “thanks” in certain contexts, “we appreciate your preference” or “we appreciate” may appear on monitored terms lists. They don’t always get blocked, but in combination with other factors (new seller, first transaction) they can trigger alerts.
The reason is subtle: Mercado Libre prefers that the transaction cycle be clearly completed before the seller closes the communication. A premature thank-you can be interpreted as early closure to avoid disputes.
Category 6 — Legal and Commercial Terms Out of Context
Words like legal, clarification, advisory, claim in certain contexts can trigger alerts because the system associates them with attempts at informal legal pressure or off-platform documentation. Terms like “business hours” or “Monday through Friday” may also appear on monitoring lists when the context involves an active dispute.
What Happens When Mercado Libre Detects a Banned Word
The flow is as follows:
- Message held: the message doesn’t reach the recipient. It stays in “pending review” status.
- Seller notification: in some cases, the system informs that the message wasn’t delivered. In others, there’s no clear notification.
- Alert accumulation: each violation adds to an internal history. The first few cases rarely generate a direct sanction.
- Formal warning: with repeated violations, Mercado Libre may issue an official warning visible in the seller panel.
- Account restrictions: in cases of sustained pattern (especially attempts to redirect to external channels), the account may face restrictions on sending messages or even be sanctioned.
An important detail: Mercado Libre doesn’t publish the complete list of blocked words. The data circulating in the seller community (and what can be inferred from tools like automatic messaging ones) shows a set of terms that changes periodically.
How to Rewrite Messages Without Losing Meaning
The good news is that in almost every case there’s an alternative wording that communicates exactly the same thing without triggering any filter. Here are five practical examples:
Example 1: Shipping notification
- Original message: “Your order has been shipped. Feel free to contact me with any questions.”
- Safe version: “Your request has been dispatched. You can follow progress from the purchases section.”
Example 2: Post-purchase thank-you
- Original message: “Thank you for your purchase. We hope you’re satisfied.”
- Safe version: “We value your choice. We hope the product exceeds your expectations.”
Example 3: Confirmed delivery
- Original message: “The product has been delivered. Please confirm receipt.”
- Safe version: “The product has been received according to the system. We invite you to share your experience in the rating.”
Example 4: Handling a concern
- Original message: “If you have any problem or question, contact me before opening a claim.”
- Safe version: “If you need guidance about the product, we respond in the platform’s chat.”
Example 5: Business hours
- Original message: “We respond Monday through Friday during business hours.”
- Safe version: “We respond on business days within the platform’s standard timeframes.”
Building a Safe Message Library
The definitive solution isn’t memorizing which words to avoid — it’s building a personal library of messages that have already been verified. Here’s how to build it:
Step 1: Take your 10 most frequent types of messages (shipping confirmation, delivery confirmed, question about guarantee, etc.).
Step 2: Rewrite each one using the safe-language principles in this guide.
Step 3: If you use an automatic messaging tool, use one with a real-time banned word detector — it checks before saving the template.
Step 4: Keep a log of messages that were held or generated warnings. Each one is training data to improve your library.
Step 5: Review your library quarterly. Mercado Libre updates its filters periodically; what was safe 6 months ago may not be today.
Conclusion
Mercado Libre’s banned word filter is a system designed to protect the ecosystem, not to punish sellers randomly. Understanding how it works lets you write messages that reach their destination, communicate what you need to communicate, and don’t put your account at risk.
The key is not thinking in terms of “which words to avoid” — it’s building the habit of writing clear, neutral messages that don’t try to take the buyer off the platform or pressure them in any way. That style of communication, besides being filter-safe, also tends to generate better buyer experiences.
If you want a tool that checks your messages before they go out, MercadoliderPro includes real-time banned word detection in all its plans. See plans.
You might also be interested in: How to Answer Questions on Mercado Libre Without Losing Sales and Best Tools to Automate Messages on Mercado Libre.