Opt-Out and Blacklist in Mumble

Summary

Customer consent to receive business messages (opt-in) is a Meta requirement. In Mumble every customer is marked as opted in or not, and when a customer taps an opt-out button in a marketing message, they are automatically moved to the blacklist and will no longer receive message templates. This article explains the indicator on the customer card, the automatic opt-out mechanism through message templates, the opt-out buttons approved by Meta, and the setting that controls the default.

Why opt-in matters for the account

Sending to a customer who asked to opt out is a direct violation of Meta’s policy, and the consequences accumulate:

Damage to your Quality Rating. Customers who asked to opt out and received a message anyway will report or block the business. Every such report lowers your Quality Rating at Meta. See Quality Rating, the complete guide.
Risk of account restriction. Meta tracks the report rate. A high rate leads to a restriction and, in severe cases, to a block of the WABA. See Bans and restrictions on a WhatsApp Business Account.
Legal exposure. In many countries (including Israel and the EU), sending without consent violates spam laws and can lead to lawsuits.

In Mumble the mechanism is automatic: a customer who taps an opt-out button in a message template goes straight to the blacklist with no manual action. Understanding the mechanism lets you work with it correctly and not bypass it by mistake.

What Meta’s policy says about opt-in

Meta requires documented, explicit consent before sending the first message to a customer outside the conversation window (24 hours). These are the consent methods Meta accepts:

The customer fills out a form with a checkbox that is not pre-checked, and actively selects “I want to receive WhatsApp updates from [business name].”
The customer sends the first message to the business.
The customer initiates a conversation through a WhatsApp link, a QR code, or a widget on the business’s website.
Verbal consent documented by a human agent (a high bar, must be documented in detail).

What does not count as valid consent according to Meta:

A pre-checked checkbox. Meta explicitly states this is invalid.
General consent in terms of use or a privacy policy, without a separate choice for WhatsApp.
Lists that were purchased, collected from public databases, or gathered from unclear sources.

The consent wording must be clear: the customer has to understand that they are choosing to receive business messages on WhatsApp from the specific business. Sending based on invalid consent puts your template approval, your Quality Rating, and in severe cases the account itself at risk.

The “opt-in” indicator on the customer card

When you open a conversation with a customer, the customer card (left panel) shows a status called “opt-in” next to the basic details:

Green check. The customer agreed to receive message templates. You can include them in campaigns.
Disabled (no check). The customer is on the blacklist. You cannot send them message templates, even if they are included in a list selected for a campaign.

It is important to distinguish between two different mechanisms that appear on the same card:

Opt-in versus the 24-hour window
Opt-in	24-hour window
A matter of consent	A matter of time
Determines whether you may send a message template at all	Determines whether you may send a free-form message (not a message template)
Shown as a green check or a disabled status	Shown mainly as a red lock icon when the window is closed
Persists until actively changed	Closes 24 hours after the customer’s last message

The two mechanisms operate in parallel. Even if the 24-hour window is open, a blacklisted customer will not receive a message template. And even if the customer has opted in, the conversation window may be closed and you will need to send a message template to reopen it.

How a customer ends up on the blacklist

1. Tapping an opt-out button in a message template

The most common and automatic way. When a marketing message template includes a Quick Reply button with an approved opt-out word (for example “Remove me,” “Stop,” “Unsubscribe”), the customer tapping the button automatically moves them to the blacklist. Mumble handles this in the background with no further action needed.

2. Manual removal on the customer card

On the customer card you can remove the “opt-in” mark manually. Useful when a customer asks to stop receiving messages by phone, by email, or in a regular conversation.

3. Importing a contact file with a status

When importing a CSV, if a negative messaging status is included in the file, the customer is imported straight to the blacklist. The exact format of the consent column depends on the account’s import template, so it is recommended to start from a sample file. See Importing and uploading contacts.

4. Through Dolores AI, the chatbot, or an automation

You can configure Dolores AI, the chatbot, or automation rules to automatically remove customers who say they want to stop receiving messages. An action to change customer status or remove them from campaign lists can be part of the system’s response.

Opt-out buttons in message templates

When creating a marketing message template, Mumble lets you add a Quick Reply button that serves as an opt-out path. The button connects automatically to the blacklist mechanism in the system.

Approved-word selector

When adding a Quick Reply button in the message template editor, there is a special selector with a list of approved opt-out words. The selector:

Shows only words in the language selected for the message template (Hebrew, English, Arabic, German, French, Italian, Russian).
Automatically fills in the button text and the message footer (“Reply X to opt out,” or in the relevant language).
Every word on the list is automatically recognized by Mumble as an opt-out request, and moves the customer to the blacklist in one tap.

Why not write free text on the button

Technically you can enter free text on the button such as “Stop” or “Please remove me.” It will look like an opt-out button to the customer, but it will not trigger the automatic blacklist mechanism. The customer taps, thinks they asked to opt out, and keeps receiving messages in the next campaigns. The result: the customer blocks or reports spam on the next round, both of which hurt your Quality Rating. Using the approved-word selector is the difference between an opt-out path that works and one that only looks like it works.

Setting the default opt-in

In the account settings there is a field called “opt-in” that controls the default opt-in status for new customers added to the account. Two options:

Opted in by default (Opt-out). Every new customer added is treated as opted in, unless they explicitly choose to opt out. Suitable only when all customer sources provide documented consent that is valid under Meta’s rules (a form with a checkbox that is not pre-checked, a customer-initiated inquiry, and so on).
Not opted in by default (Opt-in). Every new customer is treated as not opted in, unless they give explicit consent. This is the default that aligns with Meta’s requirement for explicit opt-in, and therefore the safe choice for most businesses.

If your customer sources are mixed (an old CSV import, manual entry, an initial WhatsApp interaction without explicit consent), it is better to default to not opted in with an active consent process for each customer. The setting affects only new customers from the moment of the change onward; existing customers are not changed automatically.

Returning a customer to the mailing list

A customer who dropped to the blacklist is not blocked permanently. They can return in several ways:

The customer comes back and sends a message. An active message from the customer to the business opens a 24-hour window for communication, but does not automatically restore opt-in if it was removed. New explicit consent is required to resume receiving marketing messages.
An agent restores it manually. If the customer explicitly said they want to start receiving messages again, an agent can restore the “opt-in” mark on the customer card. It is advisable to document the request in the customer notes.
A renewed opt-in process. In complex cases (for example, customers who were removed long ago and you want to bring back), you can run a campaign on a small group with an explicit consent request. Only customers who respond affirmatively are moved back to the mailing list.

Best practices

Add a built-in opt-out button to every marketing message template. Use the approved-word selector, not free text.
Do not use the Utility category to bypass opt-out. A common temptation: “The customer asked to opt out of marketing, but I’ll send them a Utility message because it’s not marketing.” If the content is genuinely promotional, it will be experienced as spam even in the Utility category. Opting out of marketing means opting out of all promotional communication, including promotional content disguised as Utility.
Check the blacklist before large campaigns. Make sure no blacklisted customer appears in an active mailing list. Mumble will prevent sending to them, but it skews the statistics and complicates the analysis.
Document manual opt-out requests. When a customer asks to opt out manually, add a note on the customer card with the date and the reason. If the customer later claims they did not ask to opt out, the documentation will remain.
Use lists for detailed segmentation. Instead of one large campaign to all customers, divide into lists by area of interest. A customer interested only in certain products can stay on some of the lists without experiencing fatigue.
Do not add numbers without documented consent. A purchased list, numbers collected from a public database, or contacts from prior years without renewed consent all hurt your rating and put the account at risk. A small, high-quality list is better.

Common issues

A customer complains that they keep getting messages even though they asked to opt out

Check the customer card. If “opt-in” is still marked, the customer may have tapped a button that was set with free text instead of an approved word. Remove the mark manually, apologize to the customer, and update your next message templates to use the approved-word selector.

Why was the campaign sent to fewer recipients than I selected?

This is an indication that some of the recipients are on the blacklist. Mumble filters them out of the campaign automatically. The campaign report will show a gap between the number of recipients selected and the number of messages actually sent. This is normal behavior.

I imported a new contact file and they do not appear as opted in

Check the “opt-in” setting in the account settings. If it is set to Opt-in (not opted in by default), every new customer is added without opt-in. You can update the status as part of the import (a dedicated column in the CSV) or mark it manually, subject to having valid consent from the customer.

How do I know how many customers are on the blacklist?

On the customer management page you can filter by opt-in status. The “not opted in” filter will show all customers on the blacklist.

A customer comes back with a message asking why they no longer receive messages. How do I return them to the list?

On the customer card, re-mark “opt-in.” Add a note with the date and the details of the request. Send a confirmation message to the customer confirming they have been returned to the list.

A campaign went out to certain customers even though they are on the blacklist

This should not happen. If it did, contact Mumble support with the details of the campaign and the specific customers. It may be a customer who left and returned to the list quickly, or a sync delay between the blacklist and the campaign system.

How do I know whether the customer tapped the opt-out button or was removed another way?

On the customer card, if the change came from tapping an opt-out button in a message template, it will appear in the conversation history. If the change was made manually by an agent, it will appear in the agent’s action history. The distinction matters because the two actions signify different things.

Compliance and spam laws

Mumble’s blacklist mechanism is an important part of meeting the requirements, but it is not enough on its own. The business owner’s responsibility includes:

The source of consent. Every customer on the list should have documentation of how they consented (a form on the site with a checkbox that is not pre-checked, signing up in a physical store, a WhatsApp conversation the customer initiated, and so on).
Prompt handling of manual opt-out requests. A request that reaches an agent by phone or email must be carried out immediately. A delay of days is a violation.
Mentioning the opt-out path in the first communication. In the first message to the customer (including a welcome message), mention the option to opt out.
An accessible privacy policy. The business website should have a privacy policy that explains the use of customer data, including communication on WhatsApp.

Bottom line

Honoring customers’ “stop” keeps your Quality Rating healthy and the account active; using the approved-word selector in every marketing message ensures the automatic opt-out mechanism actually works.

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Opt-Out and Blacklist: Managing Customer Consent in Mumble

Mumble Team