How To Opt Out of Slack AI Training

Quick Story Summary

Slack began using workspace data (messages, files, and content) to train its machine learning models without explicit user consent.
Users were automatically opted in, with no in-app notification or settings toggle to disable data usage.
The only way to opt out is by submitting a manual email request, which must be sent by a Workspace Owner or Primary Owner.
Opting out stops future model training on your data but does not delete any data Slack already holds.
The policy raised concerns around privacy, compliance (especially in regulated industries), and lack of user control.
Slack’s separate paid “Slack AI” feature does not train large language models on customer data and operates differently from these default ML systems.

Opt-out method Email request only

User control Admin required

Data retained Not deleted by opt-out

Slack introduced AI features to its platform and began using workspace data (including messages, files, and content) to train its AI models. Every user was opted in automatically, with no notification and no easy way out.

In this guide, we’ll show you exactly how to opt out of Slack AI training and stop it from using your data.

What Is Slack’s AI Training Policy?

Slack uses customer data to train machine learning models that power features like channel recommendations, emoji suggestions, and search results. When this policy came to light in May 2024, it caused significant backlash, not just because of the data usage itself, but because of how it was handled.

Users were never asked. The opt-out was buried in a privacy policy, and the only way to stop it is to send a manual email request. There is no toggle in settings, no in-app notification, and no opt-in prompt.

Why Should You Opt Out?

Your private conversations at work are being used to improve a commercial product, without your explicit consent. Even if Slack’s technical safeguards hold up, there are real reasons to push back:

Privacy: Messages between colleagues, clients, and teams are not public data.
Compliance: Businesses in regulated sectors like healthcare, legal, or finance may have strict obligations around how their data is used.
Principle: You should decide what your data is used for, not have to chase down a way to stop it.

Steps to Opt Out of Slack AI Training

There’s one important thing to know before you start: individual users cannot opt out themselves. Only a Workspace Owner or Primary Owner can submit the request.

Here’s what needs to happen:

Step 1: Contact your Slack Workspace Admin or Owner and let them know you’d like the workspace opted out of Slack’s global AI model training.

Step 2: The Workspace Owner sends an email to Slack with the following details:

To: feedback@slack.com
Subject: Slack Global model opt-out request
Body: Your workspace URL in the format yourorgname.slack.com

Step 3: Wait for confirmation. Slack will process the request and send a confirmation email once the opt-out has been completed.

That’s it. No dashboard, no settings page. Just an email to a generic inbox, using a very specific subject line.

Does This Mean Slack No Longer Has My Data?

No. Opting out stops Slack from using your workspace data to train its global models going forward. It does not delete the data Slack already holds.

To have your personal data removed, you would need to delete your account and submit a separate data deletion request to Slack directly.

What About Slack AI (the Paid Add-On)?

Slack AI is a separately purchased feature that uses large language models to summarise conversations and run AI-powered search. Slack has confirmed that it does not train those LLMs on customer data. They run on third-party models hosted within Slack’s own infrastructure.

The opt-out covered in this guide applies to the non-generative ML models (recommendations, search, emoji suggestions) that all workspaces are enrolled in by default.

Take Back Control of Your Data

Slack is one of many platforms that enrolls users in data practices they haven’t explicitly agreed to (and are often unaware of). The opt-out process is deliberately inconvenient, but it exists and it’s worth using.

If you manage a workspace, it takes five minutes. If you’re a regular user, forward this guide to whoever runs your Slack and ask them to submit the request.

Want to go further? Redact helps you find and remove your personal data from a massive range of major social media and productivity platforms – like Twitter, Facebook, Discord, Reddit, Instagram, and more.w