Apple Watch's blood oxygen feature returns after 2 years

Technology Aug 17, 2025

Apple just brought back the Blood Oxygen feature for Watch Series 9, Series 10, and Ultra 2 models in the US.
After being disabled due to a patent dispute with Masimo, it's now available again thanks to new updates—just install iOS 18.6.1 and watchOS 11.6.1 to get it working.

How to use the feature

With this feature, your Apple Watch collects sensor data, which is measured and calculated on your paired iPhone. The results sync to your iPhone's Health app under Respiratory.
The comeback was cleared by a recent US Customs ruling, letting Apple keep selling these Watches in the States.
If you're outside the US or already had this feature before, nothing changes for you—just update if you want these health insights!