Blood Oxygen Sensing Is Finally Returning to the Apple Watch

If you have an Apple Watch Series 9, 10, or Ultra Watch 2 that you bought in the US in the past year, you’ll finally get the blood oxygen sensing feature back via a software update later today, according to Apple.

To make sure you get the feature, update your paired iPhone to iOS 18.6.1 and the Apple Watch to watchOS 11.6.1. Sensor data will be calculated in the app, and you will be able to see your blood oxygen in the Respiratory section of the Health app. If you bought your watch before 2024 or outside of the US, you won’t see any changes.

A recent US Customs ruling resolved a years-long dispute with health tech company Masimo. In 2021, Masimo sued Apple, claiming the Apple Watch maker infringed on one of its patents for optical blood monitoring. A judge ruled that Apple infringed on the patent, and the International Trade Commission upheld that ruling.

Apple was forced to suspend sales of the two offending products from 2023 to 2024. When the company launched the Apple Watch Series 10 on its landmark 10th anniversary, it did so without the blood oxygen sensing feature. This feature was originally launched on the Watch Series 6 in 2020 and has since become a core feature on almost every fitness tracker.

Apple says it “redesigned” the feature but didn’t share more details. This update fixes the single biggest problem on Apple’s latest watches. Many other fitness trackers, like Garmin, have included a blood oxygen sensing feature for years. High-end trackers use the sensor data to help athletes train at altitude for optimum performance, but the feature became more important during the Covid-19 pandemic.

You might not necessarily notice your blood oxygen level dipping, but your watch can. Sales of pulse oximeters skyrocketed. I myself realized that my cough was pneumonia when my blood oxygen level started dipping to around 84 percent. (An abnormal blood oxygen rating is not enough information to diagnose illness, and you should see a doctor if you get a worrisome reading from your device.)

This is a positive development for Apple ahead of its annual September event, where it’s expected to debut new iPhones and the Apple Watch Series 11, which will inevitably introduce more extensive health features.