Calendar freezes on making edits post iOS 18 update

Calendar on iPhone 14 Pro with iOS 18.0 and on MacBook Pro M1 Pro with MacOS 15.0 both freeze when attempting to leave changes to an event in Calendar, including a new event. I've found that if I wait 10-15 minutes, the freezing will finally give way to saving the data and I can use the app again. It's a crazy long time to change the time of an appointment or to create a new one. It's usable in only the direst of situations. Who has 10 minutes to wait for it unfreeze? I've reported it to Apple, but no response.

After spending a few hours with Apple support yesterday, we were unable to solve the Google calendar syncing issues. Apparently this is a known issue that their engineers are working on. I'm still unable to add any events without the app freezing. Sometimes it results in the app showing Oct 1-12 and nothing else, no events, etc. The bottom half of the screen is blank. See photo. This is what I currently see.

This was also affecting my Google contacts, as I noticed most of my contacts were missing. After a number of unsuccessful attempts, we were able to delete my google account and re-add it to the iphone. (it kept freezing up when we would try to delete the account). After adding it back on, most (not all) of my Google contacts came back. I once again readded my Google account and was successful at getting my contacts back.

Me, too. Upgraded my IPhone 15 Pro to iOS 18 & immediately had problems with the calendar as you described. Also eats up my battery (drained it completely < 3 hours at work). I also have NordVPN running. Didn’t sweat it too much at the time because my iPhone 16 Pro was due to arrive. But it too has the exact same issues.

My calendar is useless to use on any format…I run a combo of iCloud (family shared and not) plus my work’s exchange account. I’ve tried disabling combinations w/o success. I need a new update, I guess. I’m now venturing out to 3rd party calendar solutions. By far and away my worst transition between iOS updates and/or new phone upgrades. iPad, M4 Pro 11” was also upgraded and experiencing calendar freezing issues too.

I might need to see about downgrading my new iPhone 16 Pro to iOS 17, but that worries me since my new phone was obviously designed with iOS 18 for its operating system.

Minor update as I try to solve my calendar problems. I do have an Exchange account (my work) that connects via 3rd party app for two-party authentication (Hub by VMWare). I have another iPad on iOS 18 that is not connected to my Exchange account. I was able to operate my iOS calendar with normal functions (doesn’t freeze up).

Update: Calendar app on iOS 18.0 on iPhone 14 Pro began working properly this afternoon without delay. Must be because of a change in Apple's servers. Calendar on MacOS 15.0 still has lengthy delay and is not fixed yet.

Happy to report I just updated my iPhone 15 Pro Max to iOS 18.1 and 13" iPad M4 to iPadOS 18.1. Full disclosure I only tried adding a few test events to our family shared iCloud calendar on each device and modifying a few existing events but so far no freezes. Hope to see that the battery drain issue with increased calendar activity in the background has resolved too and will report back when I have enough data.

Major I would say. Was suspicious that was the issue as coincident with the exchange email sync issue. Unfortunately use my exchange account for everything except the calendar so hope it’s solved with 18.0.1 and soon.

Guess I was under the delusional impression that they monitored this group. When you say you reset it totally do you mean you reset and restored from an iCloud backup or indeed started completely over?

FYI found another post where reseting the iPad did not solve the calendar freezing issue although no specifics on whether was restored from backup or scratch. Hate to go through all that work particularly all my authenticator apps if not successful and if a iOS patch solves the issue. Calendar freezes on iOS 18 - Apple Community

I also did the ios18 update and absolutely hate what they’ve done to the calander. When trying to input time you we’re able to activate the keypad and input the time instead of the wheel. But, now when you try to input the time using the keypad it makes you hit the hour and minute necessary separately to input and even then that doesn’t work seamlessly! I hate this new downdate!

The hang/CPU utilization was so bad for me I’ve been unable to remove the Exchange account. Charging also stopped due to overheating. Calendar even hung when simply tapping OK to acknowledge notification of an expected appointment.

Thank you for your help, Tully. I had two Exchange accounts plus iCloud for Calendar events, but after deleting both Exchange accounts, and even other Exchange accounts not relating to my Calendar, the problems remain the same on my MacBook Pro M1 Pro. Did you have any other Apple devices with your Exchange account connected to your Calendar? I'm wondering if all Exchange accounts from all Apple devices on the account must be deleted before Calendar on any Apple device will work properly. This is a problem that Apple has created, not Microsoft, but Apple is not moving fast enough to resolve it. Even MacOS 15.01 has the same issue.