How to Automatically Send a Slack Message when an Outlook Email Arrives using Power Automate

If you use Microsoft Outlook for external communication with clients but rely on Slack for internal team messaging, you likely find yourself constantly forwarding important emails to specific Slack channels. This manual bridging of two different platforms creates a bottleneck, especially for high-priority messages like server alerts, VIP customer support tickets, or urgent billing issues that your entire team needs to see immediately.

You can completely eliminate this manual work by connecting the two services using Microsoft Power Automate (formerly Microsoft Flow). Because Power Automate is deeply integrated into the Office 365 ecosystem, it can instantly read your incoming Outlook emails and automatically post the subject and body to any Slack channel of your choosing, all without writing a single line of code.

Setting Up the Power Automate Flow

To begin, you will need active logins for both your Microsoft 365 account and your company’s Slack workspace.

1. Open your web browser and navigate to make.powerautomate.com. Log in with your Microsoft credentials.
2. On the left-hand navigation menu, click on Create.
3. Select Automated cloud flow. (This means the automation will trigger instantly when an event happens, rather than on a schedule).
4. A popup window will appear. Give your flow a descriptive name, like “Outlook to Slack Urgent Forwarder”.
5. In the “Choose your flow’s trigger” search box, type Office 365 Outlook.
6. From the list of triggers, select When a new email arrives (V3), then click the blue Create button.

Configuring the Outlook Trigger

You now need to tell Power Automate exactly which emails it should be looking for. You do not want every single marketing newsletter forwarded to your Slack channel.

1. You are now in the visual flow designer. Click on the When a new email arrives (V3) box to expand its settings.
2. By default, it monitors your “Inbox”. You can click the Show advanced options button to add specific filters.
3. For example, you can enter a specific email address in the From field (e.g., [email protected]) or a specific word in the Subject Filter field (e.g., [URGENT]). The flow will now ignore all emails except those that perfectly match these rules.

Connecting to Slack

With the trigger set, you must now define the action—what happens when that specific email arrives.

1. Below your Outlook box, click the + New step button.
2. In the search box, type Slack.
3. From the list of actions, select Post message (V2).
4. If this is your first time connecting Slack to Power Automate, you will be prompted to sign in to your Slack workspace. Follow the prompts to authorise the connection.
5. Once connected, select the specific Slack Channel Name where you want the message to appear (e.g., #support-alerts).
6. In the Message Text box, you can type your own custom text and insert dynamic data pulled directly from the email. For example, you could type: New Alert Received: and then click the dynamic Subject button from the popup menu, followed by the dynamic Body button on the next line.
7. Finally, click the Save button in the top right corner of the screen.

Your automation is now live. The next time an email arrives in your Outlook inbox that matches your specific criteria, Power Automate will instantly grab the data and post it into your Slack channel, ensuring your team never misses an urgent update.