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

Similar questions

57 replies

Oct 23, 2025 6:08 AM in response to Ingo2711

No i did not try.

Dec 2, 2025 9:39 AM in response to LD150

I do not have dark skin or tatoos.

one finger fit tightly between strap and wirst.

Dec 2, 2025 2:05 PM in response to Ingo2711

No difference between the various seasons or temperatures; the issue occurred in cold weather (10–20°F), in hot weather (95-105°F), and most recently yesterday at 34°F.

Dec 3, 2025 12:32 PM in response to Ingo2711

Unfortunately, I haven’t tried yet because I don’t have a bicycle here with me. I’ll try when I get back home.

Jan 29, 2026 4:34 AM in response to steve626

Yes I demonstrated through video and pictures and anyhow they found nothing wrong with the watch.
More than one year with the same issue with n.2 different watches. Unbelivable

Jan 30, 2026 7:54 AM in response to steve626

The watch does not have any hardware issues; this is the third Ultra watch with the same problem.

I would be glad to upload a picture, but I’m unable to do so because I keep getting an error.

Feb 16, 2026 9:02 AM in response to Gabriele-Coren

Problem still present, today i had same issue. latest update did not solve it.

Dec 2, 2025 9:49 AM in response to Gabriele-Coren

Looking back, has it been more constant in the summer, when it is warmer outside?

If you are running or walking outside in the wintertime, your blood vessels will retreat and the sensor can have problems detecting your heart rate.

Dec 3, 2025 12:30 PM in response to LD150

Absolutely not, the workout is not paused, because the timer is active and counting the elapsed time. The problem starts the exact moment I begin the workout. Today, for example, it took longer than usual to detect the heart rate, but in the meantime calories, distance, and time were being counted.

Other times, everything stays at zero. The only way to fix it is to turn the watch off and on again.

Same exact problem on 3 different watches ULTRA, n.2 Ultra 2, and now with the new Ultra 3. It’s definitely a software issue, not a hardware one.

This issue drive me crazy, I’ve been in contact with Apple for more than a year, and they always ask me to wait for the next iOS update. After the update, the problem actually disappears, but then it comes back after a few weeks, with increasingly shorter intervals, until it happens almost every other day.

Dec 22, 2025 5:30 AM in response to Gabriele-Coren

Last Saturday, just two days after the previous time I had issues, it happened again but differently from all the previous times. The heart rate was read for a few seconds, then it froze and the value stayed in a fixed gray tone at the last reading, while distance and calories remained at zero even though I had covered almost half a mile.

Dec 2, 2025 9:41 AM in response to Ingo2711

i have issues only during outdoor walk or run. Indoor on treadmill no issues.

Dec 17, 2025 1:28 PM in response to Gabriele-Coren

Any update? I still have issues with IOS 26.2

This thread has been closed by the system or the community team. You may vote for any posts you find helpful, or search the Community for additional answers.

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