Persistent Heart Rate Monitoring Issue on Apple Watch Ultra 2 & 3

For the past year, I have been reporting a recurring issue related to heart rate monitoring on my Apple Watch Ultra 2, and now the same problem is occurring on the Ultra 3. Despite multiple iOS updates and the replacement of the Ultra, the issue persists.

The malfunction occurs exclusively during outdoor workouts (typically walking or running). With both devices, the issue generally begins approximately three weeks after the watches were purchased, then escalates to weekly occurrences, and then becomes almost every two days.

The only temporary workaround is to turn it off and on. Notably, ECG and other heart rate measurements function correctly outside of workouts. However, when the heart rate is not detected during a workout, the watch fails to display distance and calories.

Additionally, since the latest iOS 26 update, notifications during workouts are no longer functioning, despite being enabled.

Apple Watch Ultra 3, watchOS 26

Posted on Oct 22, 2025 9:34 AM

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57 replies

Jan 22, 2026 11:53 AM in response to steve626

In my case, during an outdoor walk or run, when I start the workout the heart rate is not detected at all. Two dashes appear with an animated red heart, and it stays that way the entire time. Distance and calories show 0.

If, on the other hand, distance and calories are counted and measured but the heart rate is not, after a few seconds the heart rate is detected; in that case, it’s just a delay. However, normally, when the issue does not occur, the heart rate is detected after a few seconds anyway.

steve626

Level 6

18,553 points

Jan 29, 2026 9:00 AM in response to Gabriele-Coren

I guess I am out of ideas for you at this point. It seems that your watch could have a faulty chip that mostly works but sometimes malfunctions. But that's an unusual failure mode for integrated circuits, in my experience as an engineer. Also, you have seen this with multiple devices. I am wondering if you might be better off with a different brand of watch, much as I hate to suggest that, I love my Apple Watch. However, in my looking online, I found similar complaints from users of other makes of exercise watches as well. These are expensive "experiments" because these devices are pricey, however.

steve626

Level 6

18,553 points

Feb 2, 2026 7:38 AM in response to Gabriele-Coren

Gabriele-Coren wrote:

I think that if the anatomy of my body were not compatible with the Apple Watch, then this issue should occur with any type of activity, whether indoor or outdoor. Instead, it happens randomly only with one specific workout. I never have any problems on the treadmill, indoor bike, at the gym, or when cycling. It only happens with outdoor walking or running, and always at the moment I start the workout. Therefore, I believe my physical has nothing to do with the problem.

It's the unique combination of the Apple Watch hardware, software, sensors, and your specific physiology, how all those things come together and interact. The fact that you have seen this with multiple watch units seems to indicate that it is not specific to one device. But the general Apple "method" (algorithms, sensors, software, hardware) are likely similar for different Apple devices. What you have experienced may be indicating that it is time to explore other brands to find one that works better for you. Some people have experienced something similar to you with other grand devices as well. Frankly, given what has to happen to detect and reliably measure a heart rate from something on one's wrist with movement, jiggling, etc. I'm surprised it doesn't work a lot worse than it does.

Apr 6, 2026 1:14 PM in response to Gabriele-Coren

new update, With iOS 26.3 the issue occurred only once, and I was quite happy because it felt like we were almost close to perfection. With iOS 26.4 things have gone back to the same levels as before iOS 26.3, therefore terrible. In addition, I am experiencing several other problems such as reduced battery life, difficulty pairing with gym equipment (in multiple gyms), and it no longer switches automatically to Sleep mode. Basically, this update is a disaster.

Dec 1, 2025 1:17 PM in response to Gabriele-Coren

I am still experiencing the same problem, which occurred again this morning. It is becoming increasingly frustrating. Despite multiple calls and having sent the watch for service (where no issues were detected), the problem continues to occur several times per week.

I have noticed that many other users report the same issue in the community.

I have tried changing wrists and adjusting the position, but nothing resolves the problem.

This issue only occurs during outdoor running sessions.

At this point, I am unsure what else to do.

Jan 10, 2026 5:28 AM in response to Gabriele-Coren

This situation has become extremely frustrating. After four months with the Ultra 3 and a year with the Ultra 2, the issue still persists. What’s most concerning is that, despite multiple reports to Apple, no action has been taken. Is anyone from Apple reviewing these cases?

Jan 12, 2026 4:33 AM in response to steve626

Heart Rate: The heart rate for outdoor runs or walks remains at zero and does not display as greyed out, as well as calories and distance.

Notifications: This is not a configuration issue; the functionality was working prior to iOS 26. An Apple representative has verified the setup, and everything is correctly configured.

Jan 17, 2026 6:59 AM in response to Gabriele-Coren

Today, like several other times this week, I experienced the same problem again. I honestly don’t know what to think or do anymore. It’s really embarrassing considering the cost of the product. With another smartwatch from a different brand (which I won’t name), costing five times less than the Ultra 2–3, I never had the slightest issue for years. With the Ultra, despite being a much higher‑end device, the problems are constant. The ridiculous thing is that Apple does nothing about it.

steve626

Level 6

18,553 points

Jan 20, 2026 11:26 AM in response to Gabriele-Coren

Gabriele-Coren wrote:

I have already taken the watches (Ultra 2–3) to Apple service, and no issues were found.

But didn't you demonstrate the malfunction you described below.

The malfunction occurs exclusively during outdoor walking or running. The issue begins immediately when I select the workout: the heart rate stays at zero, as do the distance and calories.

I don't understand how they can say "no issues were found" when your watch shows zero heart rate. Did you show that symptom to Apple service, and did they say that is "normal?"

P.S. For what it's worth, my watch (Series 11) has a simple sports band and that keeps it secure and tight to my arm.

steve626

Level 6

18,553 points

Jan 22, 2026 9:40 AM in response to Gabriele-Coren

Gabriele-Coren wrote:

I’m not sure whether the issue originates from the heart rate measurement, but it does seem so to me, since calorie calculation depends on it. As you correctly pointed out, the distance covered is linked to the GPS, which is not working during the workout.

However, the hypothesis that everything starts from the heart rate not being detected was communicated to me by Apple.

I start the workout manually myself, so it is impossible to assume that it was not initiated. Today, the issue occurred once again.

Yesterday I did a 25-mile bicycle ride, a "workout." When I started the workout, it took maybe 30 seconds for the heart rate to start showing values, and it never stopped showing values once it started. However when I look at the record of that workout by magnifying the path shown so I can see down to resolution of a foot or so, it shows me covering that distance (about 200 meters) during which the heart rate had not yet started showing. So it seems that GPS is registering changes in position and velocity even if the heart rate is not yet showing, at least on my watch. Not sure what this means or how it might relate to your issues.

Jan 22, 2026 1:57 PM in response to Jeff Donald

The main problem is that the issue occurs randomly: sometimes it happens once a day, other times it doesn’t cause any problems for weeks. If it were an issue that happened every time I went running, it would be easy to demonstrate / prove. I have sent the smartwatch in for service twice, and it was replaced with a new unit (ULTRA 2), but the glitch still persists with ULTRA 3 as well. Apple did not find anything unusual, even though I provided evidence of the problem with photos and videos. Nevertheless, after a year and a half, no solution has been provided.

Jan 30, 2026 4:41 AM in response to Jeff Donald

Contact Apple for support and service - Apple Support DONE no response

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Jeff Donald wrote:

Apple does not offer support via email or postal service. If you’re in the US, please call 1-800-MY-APPLE, or outside the US, consult the support articles below. In Canada, call 1-800-263-3394.

Contact Apple for support and service - Apple Support

Genius Bar Reservation and Apple Support Options - Apple

Explore Service Locations

Official Apple Support

I know very well Apple does not offer support via email.

Anyway, today the same problem occurred again. It has been bothering me for months now, and I don’t see a solution to it.

Feb 2, 2026 5:00 AM in response to Jeff Donald

I have already unpaired it several times, set it up as new, and I have never added any new app. Doing this makes it work for a couple of weeks, then the problem reappears. With the new update released last week, if the issue hasn’t been fixed, it shouldn’t show up for a couple of weeks (as happened with other updates), but then it will start again and occur every second day.

Feb 17, 2026 2:15 PM in response to Gabriele-Coren

How does random exclude all other variables and indicate it must be software related? Please explain the randomness of software bugs? When I encounter a software bug it’s 100% repeatable if I follow the same steps that produce an incorrect result or occurrence.

Hardware faults can be intermittent, human response can vary, human physiological response can vary, environmental conditions can vary, physical attributes of watch can vary. But software really is not a variable.

Mar 10, 2026 12:19 PM in response to Gabriele-Coren

Update on the discussion: since the release of watchOS 26.3, the issue didn’t appear for several days. This gave me hope that the update had finally resolved the problem for good. However, aside from noticing other issues I had never experienced before, late last week, yesterday, and today the **** watch once again failed to read distance, heart rate, and calculate calories. With great regret, I’m giving up to complain. I appreciate Apple for many of its products, but with their top‑of‑the‑line smartwatch they’re losing credibility. It’s absurd—I've been reporting this problem to Apple for almost two years and they’ve done nothing. At this point, I think I’ll request a replacement with another Ultra 3 device indefinitely until the problem is resolved.

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Persistent Heart Rate Monitoring Issue on Apple Watch Ultra 2 & 3