Setting Up Linked Calendars & Conflict Calendars

Modified on: Mon, 9 Jun, 2025 at 8:22 AM

HighLevel lets you synchronize external calendars (Google, Office 365, Outlook.com) to keep your availability up to date and prevent double-bookings. Use Connected Calendars to authorize HighLevel’s access, Linked Calendars to import events and show true availability, and Conflict Calendars to automatically block HighLevel slots when you have other commitments.

TABLE OF CONTENTS

When to Use Connected, Linked & Conflict Calendars
Prerequisites
Setting up the Linked Calendar
Sync Preferences (Advanced Settings)
Conflict Calendars
How these Calendars Work
Best Practices & Considerations
Common Troubleshooting
Related Articles

When to Use Connected, Linked & Conflict Calendars

Connected Calendars: Grant HighLevel permission to read (and optionally write) events from an external calendar account.
Linked Calendars: Import events and availability into HighLevel so your true busy times display.
Conflict Calendars: Mark certain connected calendars as blockers, automatically making overlapping High-Level booking slots Unavailable.

Prerequisites

User Role: Admin or Manager access in the sub-account.
External Calendar Account: Active Google Calendar, Office 365, or Outlook.com login credentials for each user.

Setting up the Linked Calendar

Step 1: Access the Connections Tab

In your HighLevel sub-account sidebar, go to Settings → Calendars, then click the Connections tab at the top to go to Calendars and Connected Calendars.

Step 2: Add a Calendar

Under Connected Calendars, click + Add New.
Select your provider: Google, Outlook, iCloud or Calendly Calendar.
Sign in and grant HighLevel permission to read events (and write, if you plan to sync bookings back).
Once successful, you’ll see your email listed with its provider icon.

Alert: Reconnect Broken Integrations
If you ever see a red banner like “Reconnect your integration” or the calendar tile is outlined in red, your OAuth token has expired or been revoked. Simply click Reconnect and re-authorize HighLevel to restore access.

Step 3: Configure Your Linked Calendar

In the Calendar Configuration section under Linked Calendar, click Add.
Choose one of your Connected Calendars to import events into HighLevel.
Click Save.

IMPORTANT:-

1. Writer's access is required for the user to select a calendar as a linked calendar. 

2. The linked calendar is by default added to the conflict calendar. This means any event created on the third-party linked calendar will be fetched in the system, and any event created in the system will be pushed to the third-party linked calendar. 

3. You can set your Sync Preferences from the Advanced Settings.

Sync Preferences (Advanced Settings)

1. Default Sync (One Way Sync)

Events created on the system will be synced to Linked Calendar (Eg, Google).
Events created on Linked Calendar (Eg, Google) will be synced to the system.
1. These events are synced as blocked slots.
2. No contact is created for guests in the Linked Calendar (Eg, Google) events.
3. No automations / workflows are triggered.

2. Two-Way Sync

Events created on the system will be synced to Linked Calendar (Eg, Google).
Events created on Linked Calendar (Eg, Google) will be synced to the system.
1. These events are synced as appointments.
2. Contact is created for the guests found in the Linked Calendar (Eg, Google) events.
3. Automation/workflows can be triggered like any other appointment created in the system.

For Example: John has created a google event from 1:00 pm to 2:00 pm called 'Doctor's Appointment with Dr. Mark' and has added Dr. Mark as a guest in his google calendar.

Default Sync (One-way Sync): Only a blocked time from 1:00 pm to 2:00 pm will be added in the system so that no one can book during that time.

Two-way Sync: An appointment is created in the system from 1:00 pm to 2:00 pm so that no one can book during that time. A new contact for Dr. Mark is created in the system. If any workflows are created, they would get triggered for Dr. Mark.

Conflict Calendars

Events from third-party calendars added as conflict calendars are synced to the system, blocking your availability for the event's duration. As the name suggests, we read all the events from the selected calendar and block off the timings when the user is not available. The availability is blocked only if the event is marked as 'BUSY' in the third-party calendar. For events marked as 'FREE', the events are fetched in the system but the availability remains open.

This ensures accurate availability and avoids double bookings. You can add multiple calendars to be checked to prevent double bookings. In the Conflict Calendars section, we do not create any appointments, instead we just block off the time for any event already scheduled in your third party calendar.

How these Calendars Work

Booking Requests
- When a client requests an appointment, HighLevel checks both your Linked and Conflict calendars. Any overlapping events render those slots Unavailable.
Two-Way Sync
- If you enable Write Back Appointments, HighLevel will write new bookings into your external calendar.
- Cancellations or reschedules in HighLevel also update your external calendar.
Calendar View
- In the Calendar tab, external events display as shaded blocks, High-Level bookings as colored events, and blocked slots as Unavailable marking.

Best Practices & Considerations

Limit Write-Back: Enable write-back on only your primary work calendar to avoid duplicate entries.
Block Personal Events: Link personal calendars as Conflict Calendars so family or personal commitments auto-block booking slots.
Align Time Zones: Ensure your external calendar’s time zone matches your HighLevel profile to prevent mismatches.
Periodic Reauthorization: If you change your external account password or security settings, reauthorize HighLevel to prevent broken integrations.

Common Troubleshooting

Issue	Cause	Resolution
Integration shows as broken (red banner)	OAuth token expired or revoked	Under Settings → Calendars → Connections, click Reconnect and re-authorize.
Events not appearing in HighLevel	No Linked Calendar selected or sync disabled	In Calendar Configuration → Linked Calendar, click Edit, ensure Sync Events is on.
Slots are still bookable during external events	Conflict Calendar is not enabled	Under Conflict Calendars, click Edit, toggle Use as Conflict Calendar, then Save.
High-level appointments are not writing back	Write-Back toggle is off	Edit your Linked Calendar settings to enable Write Back Appointments, then save.
Duplicate external events	Multiple calendars have write-back enabled	Disable write-back on secondary calendars or unlink extras you don’t need.