One of the best Apple Watch health features is now available again

One of my favourite health features on the Apple Watch (and other top smartwatches) is Blood Oxygen monitoring. It’s a really useful health metric that I monitor over time. But last year, Apple had to disable the feature from the latest Apple Watch models after briefly pulling them from sale due to a patent dispute.

Finally, after months of legal ping-pong with health brand Masimo, Apple’s finally flicked the switch to bring the Blood Oxygen feature back – albeit with a bit of a software sleight of hand. I’m glad to see the feature return, even if it took a courtroom drama and a rather clever workaround.

• Read more: Best Apple Watch in 2025 reviewed and rated

If you’ve got an Apple Watch Series 9, Series 10, or an Ultra 2 bought in the US – and your model was tragically neutered of the Blood Oxygen feature – then you’re in luck. As of today, a new free software update will give you access to a “redesigned” Blood Oxygen feature. The tech giant has managed to technically comply with the ruling while still offering the same core functionality.

Here’s how it works now: the Watch still does the sensing, but your iPhone does all the actual number crunching. Because that gets around the patent dispute. Instead of glancing at your wrist to see your SpO2 levels, you’ll now need to open the Health app on your iPhone. You’ll find them in the Respiratory section of the app. It’s not as elegant, sure, but it beats not having the feature at all. Fortunately, background measurements are still supported, so you don’t need to sit still holding your breath while it runs.

It’s also worth noting that if you bought your Apple Watch outside of the US, none of this affects you. You still have the original version of the Blood Oxygen feature with full on-device results and no changes. But if you were eyeing the Series 10 or Ultra 2 models in the US, they’re probably worth another look.

To get the redesigned Blood Oxygen feature, you’ll need to update your devices to iOS 18.6.1 and watchOS 11.6.1. It’s only available in the US for now, and only for models bought in the States with part numbers ending in LW/A. I assume it’ll be included in the first release of iOS 26 as well. If your Watch already had the feature before, you’re not losing it – and if you’re outside the U.S., you can carry on breathing easy.

• Related: watchOS 26 finally brings Apple Intelligence to the Apple Watch… for better or worse

Connor Jewiss

About

Connor is a writer for Stuff, working across the magazine and the Stuff.tv website. He has been writing for around nine years now across the web and in print too. Connor has attended the biggest tech expos, including CES, MWC, and IFA – with contributions as a judge on panels at them. He's also been interviewed as a technology expert on TV and radio by national news outlets including France24. Connor has experience with most major platforms, though does hold a place in his heart for macOS, iOS/iPadOS, electric vehicles, and smartphone tech. Just like everyone else around here, he's a fan of gadgets of all sorts. Aside from writing, Connor is involved in the startup and venture capital scene, which puts him at the front of new and exciting tech - he is always on the lookout for innovative products.

Areas of expertise

Mobile, macOS, EVs, smart home