How to Send Meeting Reminders with Power Automate

Create > Scheduled cloud flow

Create a scheduled cloud flow

Go to make.powerautomate.com and sign in with your Microsoft account. Click 'Create' in the left sidebar, then select 'Scheduled cloud flow'. Name it 'Meeting Reminders' and set it to run every 5 minutes. This frequency catches events 15 minutes before they start without missing any.

1. 1Click 'Create' in the left navigation
2. 2Select 'Scheduled cloud flow'
3. 3Name: 'Meeting Reminders'
4. 4Set repeat interval to 5 minutes

New step > Google Calendar > Get calendar view of events (V3)

Add Google Calendar connection

Click '+ New step' and search for 'Google Calendar'. Select 'Get calendar view of events (V3)'. You'll need to sign in to your Google account and grant calendar access. Choose the calendar you want to monitor - usually your primary calendar unless you have dedicated meeting calendars.

1. 1Click '+ New step'
2. 2Search 'Google Calendar' in the connector search
3. 3Select 'Get calendar view of events (V3)'
4. 4Sign in to Google and authorize access

Get calendar view of events > Parameters

Set time window for upcoming events

Configure the calendar query to find events starting in exactly 15 minutes. Set 'Start time' to addMinutes(utcNow(),15) and 'End time' to addMinutes(utcNow(),16). This 1-minute window captures events that start 15 minutes from now. Set 'Max results' to 50 to handle busy calendars.

1. 1Click in 'Start time' field
2. 2Enter expression: addMinutes(utcNow(),15)
3. 3Click in 'End time' field
4. 4Enter expression: addMinutes(utcNow(),16)
5. 5Set 'Max results' to 50

New step > Control > Condition

Add condition to check for events

Add a 'Condition' action to check if any events were found. Power Automate will still run every 5 minutes even with no events, so this prevents empty Slack messages. Set the condition to check if the length of the calendar events array is greater than 0.

1. 1Click '+ New step'
2. 2Search for 'Condition' under Control
3. 3Select 'Condition'
4. 4Set left value to length(outputs('Get_calendar_view_of_events_(V3)')?['body/value'])
5. 5Set condition to 'is greater than'
6. 6Set right value to 0

Condition Yes branch > Apply to each

Add Apply to each loop

In the 'Yes' branch, add an 'Apply to each' control to process multiple events. Set the input to the calendar events array from the previous step. This handles cases where multiple meetings start at the same 15-minute mark.

1. 1Click 'Add an action' in the Yes branch
2. 2Search for 'Apply to each'
3. 3Select 'Apply to each' under Control
4. 4Set output from previous step as input

Apply to each > New step > Slack > Post message

Connect to Slack

Inside the Apply to each loop, add a new step and search for Slack. Select 'Post message' action. Sign in to your Slack workspace and authorize the connection. You'll need to be a Slack admin or have the workspace owner approve the Power Automate app.

1. 1Click 'Add an action' inside Apply to each
2. 2Search for 'Slack'
3. 3Select 'Post message'
4. 4Sign in to Slack and authorize

Post message > Message configuration

Configure the reminder message

Select your target Slack channel from the dropdown. Build the message using dynamic content from the calendar event. Include the meeting subject, start time, meeting URL if available, and attendee list. Format it clearly so people can quickly see what meeting is starting and who should attend.

1. 1Select channel from dropdown
2. 2Click in 'Message' field
3. 3Add dynamic content for Subject, Start time
4. 4Include Join URL and Attendees if present
5. 5Format with line breaks and emojis

Apply to each > Compose > Post message

Add duplicate prevention

Add a 'Compose' action before the Slack message to create a unique identifier for each event. Use the event ID and start time to prevent duplicate notifications if the flow runs multiple times for the same event. Store this in a SharePoint list or variable for checking.

1. 1Add 'Compose' action before Slack
2. 2Set input to concat event ID and start time
3. 3Add condition to check if this combo was processed
4. 4Only send Slack message if not duplicate

Save > Test > Manually

Test with upcoming meeting

Create a test calendar event 20 minutes from now. Save and manually run your flow to test the logic. Check that it finds no events (since it looks for 15-minute window). Then wait until 15 minutes before your test meeting and let it run automatically.

1. 1Click 'Save' in top right
2. 2Click 'Test' button
3. 3Select 'Manually' and click 'Test'
4. 4Create a calendar event 20 minutes out
5. 5Run the test and verify no message sent

Flow details > Turn on > Run history

Enable and monitor the flow

Turn on the flow and monitor it for the first few runs. Check the run history to see successful executions and any failures. Watch for calendar permissions issues or Slack rate limiting with busy schedules. Set up email notifications for flow failures so you know when reminders stop working.

1. 1Click 'Turn on' to activate the flow
2. 2Go to 'Run history' tab
3. 3Monitor first few executions
4. 4Set up failure notifications in Settings

Use Power Fx expressions to format attendee emails into readable names and handle missing meeting URLs gracefully. Add this in a Compose action before your Slack message.

// Format attendees list
if(empty(items('Apply_to_each')?['attendees']), 
  'No attendees listed',

// Format attendees list
if(empty(items('Apply_to_each')?['attendees']), 
  'No attendees listed',
  join(
    select(
      items('Apply_to_each')?['attendees'],
      if(contains(item()?['displayName'], '@'),
        first(split(item()?['displayName'], '@')),
        item()?['displayName']
      )
    ),
    ', '
  )
)

// Handle meeting URLs with fallback
if(not(empty(items('Apply_to_each')?['hangoutLink'])),
  concat('🎥 ', items('Apply_to_each')?['hangoutLink']),
  if(not(empty(items('Apply_to_each')?['location'])),
    concat('📍 ', items('Apply_to_each')?['location']),
    '📅 Check calendar for details'
  )
)