How ZuniPixel Migrates Slack Private Channels and Direct Messages to Google Chat

Introduction

When an organization migrates from Slack to Google Chat, the IT admin needs to understand how Slack treats public channels differently from private channels and direct messages. The functionality looks similar, but the sensitivity and security of the conversations are not — which changes what needs to be prepared, communicated to end users, and understood about how the migration process actually works. ZuniPixel simplifies this entire process — sending the consent request, tracking the response, and initiating the migration — so IT admins can handle it smoothly.

Why private channels and DMs need special handling

Slack private channels are meant for smaller, closer groups, unlike public channels. Their purpose is to keep conversations confidential and contained within the group, rather than visible across the organization. Not everyone can view a private channel or its conversations — to join one, an existing member has to send an invite, since these channels are invitation-only. Private channels often hold an organization's most sensitive information, such as new product launches, pricing discussions, and security compliance details. For the full picture of what migrates and how, see the complete Slack to Google Chat migration guide.

Why consent is required for private channels and DMs

When migrating private channels from Slack to Google Chat, Slack doesn't provide a list of private channels the way it does for public channels — because, as mentioned, this content is highly sensitive. Even the Slack admin cannot access the list of private channels. This is a limitation on Slack's side, not ZuniPixel's. To get the list of private channels, along with their members, roles, replies, and threads, user consent is required — letting employees know that a migration to ZuniPixel is planned.

How ZuniPixel requests and tracks user consent

ZuniPixel sends an email to every user in the ZuniPixel application, using a customized email template explaining the migration decision. When a user clicks the link in the email, they're taken to Slack's login page, where they enter their credentials as they normally would. Once authenticated, ZuniPixel receives the list of private channels that the user is part of.

IT admins often worry about how to send these emails to every user and how to track who has completed authentication. ZuniPixel is built with this exact concern in mind — admins can see who the emails were sent to and who has authenticated, all from the dashboard. In practice, at least one or two follow-up emails are usually needed, since some users are on leave or simply deprioritize it. IT admins can resend the email directly from the ZuniPixel platform for anyone who hasn't responded, since the original email can easily get buried in an inbox.

What happens to DMs during migration

Direct messages are conversations that typically occur between two or more team members. In terms of sensitivity, they're on par with Slack private channels — people use DMs to have private discussions. A conversation between the CTO and CEO, or among C-suite members, is just as important and sensitive as anything shared in a private channel. The same consent requirement applies here as it does for private channels.

For a private channel, even if only one member completes authentication, ZuniPixel can retrieve the channel's details and migrate the conversation. For direct messages, whether 1:1 or group, at least one participant must authenticate for the DM to be migrated.

Private channels: membership, permissions, and edge cases

One of the most common scenarios in private channel and direct message migration is when employees have left the organization. These users become inactive and don't have a license in Google Chat, but their conversations still need to be reflected exactly as they were in Slack. Since exited employees don't get mapped during user mapping — they have no license in the destination — ZuniPixel addresses this by mapping their messages to the Google Workspace admin by default. Some organizations prefer to map these to a different user instead, and ZuniPixel discusses this during migration planning to match the customer's requirement. For all exited employees, messages are posted by the admin (or the customer's chosen user) in the destination. In Google Chat, these appear as posted by the admin or the chosen email — but the original sender's name is still labeled. To understand the complete Slack to Google Chat migration process, see our full migration guide.

What IT admins should communicate to users

Most users get confused about why they're being asked to authenticate or log in again — some may even think it's a phishing attempt. To avoid this, IT admins should let their users know the organization has decided to migrate from Slack to Google Chat, and that they'll receive an email from ZuniPixel. Sharing the actual email template in advance helps build awareness, so users recognize it when it arrives. A soft timeline — completing authentication within 3-4 days — helps users understand there's a timeframe to work within, without making it feel like a hard deadline.

Key Takeaways

• Private channels and DMs carry an organization's most sensitive conversations, so Slack requires user consent before ZuniPixel can access them — this is a Slack limitation, not a ZuniPixel one.
• ZuniPixel automates the consent process with a customized email, tracked in real time on the dashboard, with easy follow-up for anyone who hasn't authenticated.
• Only one authenticated member is needed to unlock a private channel or DM for migration — not every member.
• Departed employees' conversations still migrate and are posted through the Google Workspace admin (or a customer-chosen user), with the original sender's name labeled.
• Slack roles map to equivalent Google Space roles, preserving permissions from Space Owner down to external guest access.