Google Calendar unable to connect in Apple Calendar after iOS 26.6.1 update

Hello NiniParis and welcome to the Apple Support Community.

Your troubleshooting has already ruled out most of the usual causes. Google Calendar works normally in a browser, Gmail works, Google authentication succeeds, the account has been removed and added again, Calendars is enabled, and the same failure occurs over both Wi-Fi and cellular data.

There is also an important new development : very recent reports describe Google Calendar accounts suddenly failing to sync with third-party calendar clients, including Apple Calendar, while the same calendars continue to work normally on calendar.google.com.

Some of those reports show an HTTP 503 response from Google’s Calendar/CalDAV service.

This does not establish that iOS 26.6.1 caused the problem.

At present, there is no published Apple notice identifying a Google Calendar regression in iOS 26.6.1, and Google’s public Workspace status page is not reporting a general Calendar outage.

However, given your testing and these recent matching reports, a Google-side third-party Calendar synchronization issue is currently a credible possibility.

→ We would avoid further destructive troubleshooting for now :

• Do not erase the iPhone or reset all settings.

• Do not repeatedly remove and re-add the Google account, since you have already successfully completed that test.

• Continue using calendar.google.com for access to your calendar data while the synchronization issue persists.

→ One useful isolation test remains :

• If you have another Apple device, add or check the same Google account in Apple Calendar there.

• If the same Google account fails there while Google Calendar continues working on the web, that would further support an account/server-side synchronization problem rather than an issue specific to this iPhone.

• If another Google account works normally in Apple Calendar on this iPhone, that would also indicate that the problem follows the affected Google account rather than the Calendar app generally.

At this stage, waiting for further information from Google is more appropriate than wiping the iPhone.

You can also send feedback to Google and follow the current reports concerning third-party Calendar synchronization.

Please post back if the account begins syncing again or if Apple Calendar displays a more specific server error.

🙏

Have a good day.

And one more thing…

Never forget to think different.



Note :

The fact that this issue appeared after updating to iOS 26.6.1 does not establish that the update caused it. Recent similar reports suggest a possible Google Calendar/CalDAV synchronization issue affecting third-party calendar clients, but this has not been confirmed as a general iOS 26.6.1 issue.

Important :

• Always make sure that your Apple devices are running the latest version available of their operating system and that your apps are updated to the latest version available in order to benefit from fixes and compatibility improvements.

• Your iPhone 17 is already reported as running iOS 26.6.1, which Apple currently lists as the latest public iOS version for compatible iPhones. You can verify this in Settings > General > Software Update.

Useful links :

Change your Calendar settings on iPhone – Apple Support

Add Google Calendar events to Apple Calendar – Google Calendar Help

Google Calendar fails in Apple Calendar and Fantastical on iOS/macOS – Google Calendar Community

Hello NiniParis.

Thank you for testing this on your iPad.

That result is particularly useful : since the same Google account also fails to synchronize with Apple Calendar on a second Apple device, an issue specific to your iPhone is now much less likely.

Combined with the fact that Google Calendar continues to work normally on the web, this strengthens the possibility of an account-side or Google third-party calendar synchronization issue.

There have also been very recent reports of Google Calendar accounts failing with Apple Calendar and other third-party calendar clients while continuing to work normally through Google Calendar itself.

This still does not prove a general Google outage or establish that Google is definitely responsible, but your result is consistent with those reports.

→ You can send the feedback directly from Google Calendar on the web :

• On a computer, open calendar.google.com and sign in.

• Click Support > Send feedback.

• Explain that the same Google account works normally on calendar.google.com but fails to load in Apple Calendar on both your iPhone and iPad.

• Mention that authentication succeeds, that removing and adding the account again did not resolve it, and that both Wi-Fi and cellular data were already tested.

We would not perform any reset or erase either Apple device at this stage.

You have now reproduced the same problem on two devices, which is much more useful diagnostically than repeating the previous troubleshooting.

Please let us know if synchronization starts working again or if Google provides any information about the issue. That result could also help other users encountering the same behavior.

🙏

Have a good day.

And one more thing…

Never forget to think different.



Note :

Reproducing the problem on a second Apple device makes an iPhone-specific problem less likely, but it does not by itself prove that Google is experiencing a general service outage.

Important :

• Always make sure that your Apple devices are running the latest version available of their operating system and that your apps are updated to the latest version available in order to benefit from fixes and compatibility improvements.

• Your iPhone 17 is already reported as running iOS 26.6.1, which Apple currently lists as the latest public iOS version. You can verify software updates in Settings > General > Software Update.

Useful links :

Send feedback about Google Calendar – Google Calendar Help

Google Calendar fails in Apple Calendar and Fantastical on iOS/macOS – Google Calendar Community