Email reaches Slack in four ways, and each one suits a different job. A channel email address that Slack issues on paid plans receives every message sent to it, and the Gmail and Outlook add-ons send one message at a time. A forwarding rule in the mailbox sends everything to a channel address, and a shared inbox integration posts each conversation with buttons to act on it. The first three put a copy of the email in Slack, and the reply still has to be written in the mailbox. The fourth keeps the email in the inbox and sends Slack a notice with the owner, the status and a way to assign or close the conversation.
To forward a single email, use the Slack add-on for Gmail or Outlook, which works on every Slack plan. To send every email from an address into a channel, get the channel's email address in Slack, which needs a paid plan, and forward to it from the mailbox. To run a support or team address, connect the shared inbox tool that holds it to Slack. The channel then receives each new conversation and assignment with buttons, and the reply is written where the history lives.
The four ways email reaches Slack
| Method | Slack plan | What arrives | Where the reply is written | Fits |
|---|---|---|---|---|
| Gmail or Outlook add-on | All plans | One email at a time, sent by a person to a channel or a direct message | In the mailbox | Sharing a single email for discussion |
| Channel email address | Paid plans | Every email sent to the address, posted as a message | In the mailbox | Notifications and alerts from systems |
| Forwarding rule to a channel address | Paid plans | A copy of every email the rule matches | In the mailbox, where the original stays | Watching an address without opening the mailbox |
| Shared inbox integration | All plans | A notice per event with the owner, status and excerpt, and buttons | In the shared inbox, one click from the notice | A support or team address with owners and service levels |
How to send email to a Slack channel with a channel email address
Slack issues an email address for a channel or a direct message on paid plans, and any email sent to that address posts into the conversation. By default any channel member can get an address, and owners and admins can restrict that. The sender's name and icon can be set per address, and deleting the address stops the emails. In a Slack Connect channel, each organization's address posts emails that every member can see.
- Open the channel and click its name in the conversation header.
- On the About tab, choose Send emails to this channel, then click Get email address.
- Click Copy, and paste the address into the system that should post here or into a forwarding rule in the mailbox.
- Send a test email and check that it posts with the sender name you expect, then adjust the name or icon if needed.
The channel address is the right route for notifications, such as an alert from a monitoring tool, a receipt or a form submission. It is the wrong route for a customer address. The email arrives in Slack as a post with no owner, and the reply is written somewhere else. Within a day the thread in Slack and the thread in the mailbox have drifted apart.
How to forward an email to Slack from Gmail or Outlook
The Slack add-on for Gmail and the Slack add-in for Outlook send one email at a time to a channel or a person. Both are available on every Slack plan, including the free one. Each teammate installs the add-on and connects their own account, and a Google Workspace or Microsoft 365 administrator may need to approve it first. The Outlook add-in works with Microsoft 365 mailboxes on the Exchange protocol and does not support on-premises Exchange or mailboxes set up over POP or IMAP.
- In Gmail, install the Slack add-on from the Google Workspace Marketplace, open an email, click the Slack icon in the right sidebar and choose Connect to Slack.
- With an email open, click the Slack icon, search for a channel or person, and click Send to the name shown. The email appears in Slack with a View link.
- In the Outlook desktop app, install Slack for Outlook from Microsoft AppSource, click the Slack icon in the toolbar and choose Connect to Slack. Then open an email, click the icon, choose a channel or person and click Send to Slack.
- In Outlook on the web, open an email, click the three dots, choose Slack for Outlook to connect, and then Send to Slack on any later email.
The add-on suits the case it was built for, which is a person sharing one email so colleagues can discuss it. It does not suit a support address, since every message needs a person to forward it and the channel receives whatever that person chose to share. A team that finds itself forwarding several emails a day from one address needs one of the other routes.
Forwarding rules from a mailbox to Slack
A forwarding rule in Gmail or Outlook sends a copy of each matching email to the channel address. The channel then sees everything that arrives at the mailbox without anyone forwarding by hand. Gmail asks you to confirm the forwarding address first, and the confirmation email posts into the channel like any other. Slack also issues a personal forwarding address under Preferences, then Messages and media, which delivers forwarded emails to you as direct messages rather than to a channel.
The rule scope matters more than it looks. A rule that forwards everything posts the newsletters and the out-of-office replies along with the customer messages. A rule that forwards replies as well as new mail doubles the volume. The original stays in the mailbox, which still has to be opened to reply, and the Slack copy has no status and no owner.
A shared inbox integration that posts conversations with actions
A shared inbox tool holds the team's support or sales address and gives each conversation an owner, a status and notes. Its Slack integration posts an event, such as a new conversation or an assignment, to a channel the team chooses. The post carries the subject, an excerpt, the people on the thread and the owner. The reply is written in the inbox, where the history and the customer's record live, and the Slack post is the alert and the place to act from. The integration suits an address that several people answer and that needs ownership and service levels, which is the case the other three routes do not cover.
The problems with email in Slack: replies, threads and ownership
Three problems appear within a week on the simple routes. Replies cannot be written from Slack, so a teammate who reads an email in the channel still opens the mailbox to answer it. The answer is then invisible to the channel. Threads split, because each new email in a conversation arrives as a separate post. The discussion in Slack attaches to one of them while the customer's later message sits elsewhere. Ownership is undefined, since a post in a channel belongs to no one in particular, and a message that two people assume the other will handle is answered by neither.
The fixes are the features of a shared inbox rather than of Slack. An owner on each conversation answers the ownership question, and a status answers whether anything is waiting. A notice in Slack that links to the conversation keeps the discussion attached to the right thread. How to stop two people replying to the same email covers the collision problem on its own, and shared inbox best practices covers the rest of the routine.
How the Sektra Slack integration works
Sektra's Slack integration posts shared inbox events to the channels you map. Each mapping names a Slack channel, an inbox or every inbox, and the events to post there. The list of fourteen events includes a new conversation, an assignment, an incoming message, a reply sent, a conversation closed or reopened, and a service level warning or miss. A billing inbox can send its new conversations to one channel while service level warnings from every inbox go to another. Rules, which act on a conversation when it arrives or changes, can post to Slack as one of their actions, and the alert shows the rule's name.
Each alert opens with a line that names the event and the subject and links to the conversation. Below it are an excerpt, the inbox, the people on the thread, the status and the owner. Under those sit four buttons: Assign to me, Close, Snooze until tomorrow, and Open in Sektra. A reply posted under the alert in Slack becomes an internal note on the conversation, so a teammate can leave context without opening the inbox. Each click or reply acts as the inbox user linked to that Slack account, which a teammate sets up once with Connect my Slack account in their settings.
Connecting the two takes a few minutes and one approval. A teammate who can manage integrations opens Settings, then Integrations, and chooses Connect Slack, approves the app for the workspace, adds a channel mapping and sends a test message. The app asks Slack for permission to post messages and to list channel names, and it reads only the replies posted under its own alerts. Customer replies are still written in the inbox, from the shared address, so every answer sits in the conversation's history and the Slack channel stays a place to coordinate.
Which way to choose
Use the Gmail or Outlook add-on when one email needs a discussion, and the channel address when a system should post notifications. Use a forwarding rule when a channel should watch an address that no one opens. Use a shared inbox integration when the address is one that customers write to and several people answer. That is where replies, threads and ownership stop working on the other routes. Sektra is one such integration, and Front, Help Scout and Hiver also post inbox events to Slack, each in its own way.
Common questions
How do I forward an email to Slack?
For one email, use the Slack add-on for Gmail or Slack for Outlook: open the email, click the Slack icon, choose a channel or person and send it. For every email sent to an address, get the channel's email address in Slack, which needs a paid plan, and set a forwarding rule in the mailbox to that address.
Can I send emails to a Slack channel for free?
The Gmail and Outlook add-ons work on every Slack plan, including the free one, for sending an email at a time. A channel email address, which receives every email sent to it, is available on paid plans only.
Can I reply to an email from Slack?
Not through Slack's own email features. An email posted to a channel is a copy, and the reply is written in the mailbox. A shared inbox integration keeps the email in the inbox and posts an alert in Slack with buttons to assign, close or snooze the conversation. The reply is written in the inbox, one click away.
What is the best Slack email integration for a support team?
A support address needs an owner and a status on each conversation, which a channel email address does not provide. A shared inbox tool with a Slack integration posts each new conversation and assignment to a channel with a link back. Sektra's version adds buttons to assign, close and snooze, and turns thread replies into internal notes.
