Call Blocking (CallKit) not working on iOS 26 Public Beta

I have also tested with a factory reset device (using the debugging profile) and still the call blocking didn't work. I have attached a sysdiagnose ZIP as well in the FB bug (sysdiagnose_2025.08.05_10-45-11+0300_iPhone-OS_iPhone_23A5297m.tar.gz)

Perfect, thank you. The set of logs taken with the debug profile were particularly helpful, and the team has found the issue, which was caused by an existing, subtle difference between how communicationd and callservicesd, which other changes in underlying infrastructure then exposed. I can't provide any specific timeline or scheduling, but the bug fix is straightforward and high priority.

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Kevin Elliott
DTS Engineer, CoreOS/Hardware

That's great news!

Thank you for the thorough investigation and handling of the issue. I really appreciate the collaborative approach in getting to the root cause. I'll keep an eye on future releases and I'm happy to test this with a (possible) new beta release when the fix is implemented.

The issue persists in iOS 26 Beta 6 (Build 23A5318c). I have attached a new sysdiagnose collected from the latest build for your review in the FB bug.

I also tested on iOS 26 Beta 6 (Build 23A5318f), but blocked calls still pass through.

The issue persists in iOS 26 Beta 6 (Build 23A5318c).

As come quick follow up on this, yes, the issue is not fixed in beta 6. As some background context, there is a significant testing process before every beta is released, so it's not unusual for a bug to be completely "fixed" (meaning, all code changes have been submitted and are "in" that release) but miss the "next" beta release because that release is already locked and in testing.

I also tested on iOS 26 Beta 6 (Build 23A5318f), but blocked calls still pass through.

In a similar vein, the minor letter (c vs f) is primarily used to designate differences that are outside the actual code/build, like the distribution mechanism (in this case, the developer seed vs. the public beta). While it's possible there have been exceptions, I would not expect there to be ANY substantial behavioral difference* between those two build.

*The obvious exception would be issues caused by differences in the install or configuration pipeline, which is why we don't use exactly the same build version for both cases.

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Kevin Elliott
DTS Engineer, CoreOS/Hardware

Ok, thanks for the clarification. I’ll be waiting for the fix in the next beta (or stable) release version.

I have tested with iOS 26 Beta 7 (23A5326a) and the bug is fixed.

Calls are now blocked when a blocking rule is set with addBlockingEntryWithNextSequentialPhoneNumber from CallKit API.

I have closed the FB issue. Thanks for fixing that.

I've just tested using the new iOS 26 Beta 8 (23A5330a) and call blocking stopped working. After restarting my device following the iOS update, the issue resolved, and call blocking is working as expected on Beta 8. I don't know if it's an edge-case bug though.

I've just tested using the new iOS 26 Beta 8 (23A5330a) and call blocking stopped working.

If this happens again, please capture a sysdiagnose before rebooting and file a bug. It's likely that this was some kind of one-off glitch, but there isn't really anyway to know without the log data.

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Kevin Elliott
DTS Engineer, CoreOS/Hardware

I tested on iOS 26 Beta 8 (23A5330a) and unfortunately call blocking still doesn't work for me. I set blocking rules with addBlockingEntry(withNextSequentialPhoneNumber:) and it worked fine on iOS 18 and below (I didn't make any changes after updating to iOS 26)

I did some tests with different phone numbers. If the phone is not in the call list, it usually gets blocked, but only once. I guess this is because after the first block it still gets into the call list and therefore doesn't get blocked anymore

@Papaductions, did you test the scenarios with the phone from recent calls or blocking a call from the same number multiple times in a row? Did it work fine?