iOS 18.6.1 and watchOS 11.6.1 Released: Blood Oxygen Monitoring Returns to U.S. Apple Watches

Apple today released iOS 18.6.1 for the iPhone and watchOS 11.6.1 for the Apple Watch Series 9, Apple Watch Series 10, and Apple Watch Ultra 2. The updates re-enable blood oxygen monitoring in the United States.

Generic iOS 18
iOS 18.6.1 can be downloaded on eligible iPhones over-the-air by going to Settings > General > Software Update. watchOS 11.6.1 is available for newer Apple Watch models that have blood oxygen monitoring disabled, and it can be downloaded through the Apple Watch app on the ‌iPhone‌.

Apple said that blood oxygen monitoring is coming back to U.S. Apple Watch models due to a "recent U.S. Customs ruling."

Back in early 2024, the United States International Trade Commission (ITC) found that Apple violated blood oxygen sensing patents owned by Masimo. The ITC implemented a trade ban, and Apple had to stop selling the Apple Watch Series 9 and Apple Watch Ultra 2. Sales resumed after Apple disabled the blood oxygen monitoring feature in Apple Watch devices sold in the U.S.

Since January 2024, no Apple Watch models purchased in the U.S. have had a functioning blood oxygen sensor, including the Apple Watch Series 9, the Apple Watch Series 10, and the Apple Watch Ultra 2.

apple watch series 6 blood oxygen monitoring 1
With iOS 18.6.1 and watchOS 11.6.1, Apple is implementing a workaround. Data collected by the blood oxygen sensor on the Apple Watch will be processed on a paired ‌iPhone‌, with the results available in the Respiratory section of the Health app.

The feature typically allows users to see a readout of their blood oxygen level right on the Apple Watch, but this isn't how it will work in the U.S.

The update is designed for Apple Watch Series 9, Apple Watch Series 10, and Apple Watch Ultra 2 models sold in the U.S. that do not already have blood oxygen sensing available. Blood oxygen monitoring remained available on older watch models, and there has also been no change to Apple Watch models sold outside of the United States.

Related Forum: Apple Watch

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Top Rated Comments

btrach144 Avatar
23 weeks ago

This is so depressing to see said out loud.

Apple used IP they had no right to and you're happy about Apple "out maneuvering" the IP rights holder?
Apple is no longer using methods that infringe on IP. Not sure why that’s so hard to understand.
Score: 23 Votes (Like | Disagree)
Entilzha Avatar
23 weeks ago

Somewhat burying the lede.

This really isn't "coming back to the Watch".
Sensor capability is coming back to the watch. Whether said data is displayed ON the watch or not, the sensors are enabled again.
Score: 20 Votes (Like | Disagree)
roncron Avatar
23 weeks ago

You're really stretching here.

Ask any normal person what a feature "coming back to the Watch" means and you won't get anyone saying "that means I view the data on my iPhone"
I think a normal person would see this as:

* Before January 2024, people could buy an Apple Watch and use it to measure/monitor their SPO2 levels.
* After January 2024, people could not.
* Now, people can use Apple Watches purchased after January 2024 to measure/monitor their SP02 levels.

That people now need an iPhone to see the results is orders of magnitude less important than being able to use the Watch instead of a more bulky device to monitor their O2 levels. Everyone who owns a Watch owns an iPhone, too.

I'm also guessing a normal person would not find this debate particularly interesting, so my apologies to the normal people out there for contributing to it.
Score: 14 Votes (Like | Disagree)
archvile Avatar
23 weeks ago
Someone on reddit suggested taking an ECG to activate the blood oxygen app, I just did this and sure enough now the blood oxygen app works.

[MEDIA=reddit]AppleWatch/comments/1mq9xle/comment/n8pbthk[/MEDIA]
Score: 13 Votes (Like | Disagree)
jz0309 Avatar
23 weeks ago

This is so depressing to see said out loud.

Apple used IP they had no right to and you're happy about Apple "out maneuvering" the IP rights holder?
Massino could not convince a jury that Apple breached their patent, so they chose a roundabout way and got the ITC to ban the import of the AW with said feature - what Apple has done now I call a brilliant move.
Score: 12 Votes (Like | Disagree)
jz0309 Avatar
23 weeks ago
Great move and workaround by Apple!
Score: 12 Votes (Like | Disagree)