How to send a Slack message to email

Slack's help center covers bringing email into Slack. For the other direction, Slack's own route is a Workflow Builder step that sends an email from your Gmail or Outlook account. If the Slack message you want to send is an answer to someone who emailed you, there is a simpler way: reply in a thread that goes back to them as an email.

1. Workflow Builder's Send an email step

Slack has connector steps called Send an email for Gmail and for Outlook. Connector steps are available on paid Slack plans, and depending on your workspace an admin may need to approve the step first.

The email goes out from the account of the person running the workflow: Slack asks them to link their Google or Outlook account the first time they start it. Slack's developer reference says workflows that use the runner's own account can only be started with a link trigger, so someone starts each send.

In Slack's reference, the Gmail step's recipients are Slack user IDs matched to email addresses. The Outlook step also takes plain email addresses as additional, CC and BCC recipients, which is what you need for someone outside your workspace.

2. When the message answers a customer's email

Most Slack messages that need to become an email are replies: a customer wrote to support@, the team talked it over in Slack, and now the answer has to reach the customer. RelayMail posts each forwarded email as a Slack thread, and a reply in that thread is sent to the customer as an email, in the same conversation in their inbox. Nobody runs a workflow or copies text into a mail app.

A thread message that starts with // or note:, or with an @mention of a teammate, stays in Slack as an internal note. RelayMail is $15/month per inbox with a 14-day trial, and anyone in the channel can reply.

When Workflow Builder's email step is the better pick

×Use Workflow Builder's Send an email step if you now and then need to email a Slack message to someone, and your workspace is on a paid plan.

When RelayMail is the better pick

✓Use RelayMail if the messages you want to email are answers to people who emailed you, and every reply in the thread should go out without a workflow.

Questions

Who does the email come from?

With Workflow Builder, from the Gmail or Outlook account of the person who runs the workflow. With RelayMail the customer gets a normal email with your name that comes back to your address; after you verify your domain it is sent from your own address too.

Can I email someone outside my Slack workspace?

Yes. Slack's Outlook step takes plain email addresses. With RelayMail the recipient is the person who emailed you, so they never need Slack.

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Updated 2026-11-11. How we check these pages. Sources: