The short answer
In the sub-account, open Calendars, click Calendar Settings, go to the Connections tab, click Add New and connect Google Calendar, granting full calendar access. Then choose a linked calendar for bookings and any conflict calendars that should block time. Each team member connects their own Google account; one connection does not cover several users.
Connect your Google account
Go to Calendars in the left menu, click Calendar Settings at the top right, open the Connections tab and click + Add New. Click Connect beside Google Calendar, choose the Google account and accept every permission requested, including read and write access to calendars plus your profile and email. HighLevel warns that Google lets you untick some permissions, and partial access leads to sync failures. If that happens, look for a missing-permissions warning under Settings, Integrations, Google and click Reconnect. Personal Gmail and Google Workspace accounts both work.
Choose the linked calendar and conflict calendars
Connecting the account only grants access. Under Calendar Configuration, add a Linked Calendar: the Google calendar where HighLevel bookings are written and whose events show your real availability. You need writer access to it, and it also counts as a conflict calendar by default. Add other Google calendars, such as a personal or family one, as conflict calendars so their events block booking slots without creating appointments. Only events marked Busy in Google block time; events marked Free are read in but leave the slot open to bookings.
Pick a sync mode and fix common problems
In the sync preferences under advanced settings, the default mode sends HighLevel bookings to Google and brings Google events in as blocked time, with no contacts created and no workflows triggered. Two-way sync brings Google events in as real appointments, creates contacts for their guests and can start workflows, which only makes sense if you want those guests in your CRM. Sync usually breaks when the Google token expires, the calendar is deleted or permissions are revoked. Reconnecting fixes most cases, and HighLevel then resyncs upcoming appointments automatically. Keep the Google calendar's time zone the same as your HighLevel profile.
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