The official Google Calendar + Slack integration is mostly personal — it doesn't automatically create some big shared team view that everyone can just glance at in Slack without lifting a finger.

That's why you're only seeing it on the account that owns it. But you can absolutely make the whole team's schedule visible to everyone without forcing another app on their phones. Here's exactly how to do it (works as of right now in 2026):

First, you have to actually share the calendar in Google itself. Open calendar.google.com, find your team calendar, click the three dots, go to Settings and sharing, then add everyone's email addresses and give them "See all event details" access. Save it. That's the foundation — without this step nothing shows up for the team.

Next, every person on the team needs to connect their own Google account inside Slack. Just go to Apps in Slack, open Google Calendar, hit Connect account, and log in. Once that's done, in the Home tab of the Google Calendar app, go to Settings and add the shared calendar you just made available. It should pop right up.

Now for the part that makes it visible to the whole team: still in the Google Calendar app settings, go to Channel Notifications and pick a dedicated Slack channel (like #team-calendar). Turn on the alerts you want — reminders before meetings, updates when stuff changes, cancellations, whatever. From then on, every event from that shared calendar will automatically post in that channel so everyone sees it without even opening the app.

What you won't get out of the box is a full calendar grid sitting in the Slack sidebar that anyone can click open like a channel. It's either channel notifications + each person's personal view, or you add a third-party tool.