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How to tell if the Apple Watch you're about to buy has pulse oximetry

How to tell if your Apple Watch has pulse oximetry

Starting January 18, Apple will sell the Apple Watch Series 9 and Apple Watch Ultra 2 with pulse oximetry disabled in software. Here's how to tell if an Apple Watch has pulse oximetry or doesn't.

Apple has a how to identify your Apple Watch webpage. It's great for figuring out generally which model you have, but it still has yet to be updated with one key feature — how to tell if an Apple Watch has pulse oximetry.

There's one way to tell. Check the part number on the Apple Watch.

Apple says on its Apple Watch Ultra 2, Apple Watch Hermes, and Apple Watch Series 9 pages that "the ability to measure blood oxygen is no longer available on Apple Watch units sold by Apple in the United States after January 18, 2024. These are indicated with part numbers ending in LW/A."

You're safe if you're reading this on January 18 or within a few days or have an Apple Watch that you bought before January 18. The current ban is only on imports and sales via Apple on the device.

For now, the best way to check pre-purchase is on the device's box. There is a string of characters starting with M and ending either in LL/A or LW/A. The former has pulse oximetry, and the latter does not.

The model number is shown here, on the right side of the back of the box, towards the bottom.

Back of an Apple Watch box, showing the part number near the bottom of the box
Back of an Apple Watch box, look for the characters starting with M and ending in LL/A or LW/A

Failing the box, the unit itself can be checked if the watch is set up.

  1. Select the Settings app on the watch
  2. Tap General
  3. Tap About
  4. Scroll down to Model
  5. Tap the five-character model number that starts with A to see the full model number

If it has LW/A on the end instead of LL/A, the pulse oximetry feature is disabled in the software as a result of the import ban. This watch is an original Apple Watch Ultra, so obviously, it has pulse oximetry.

Apple Watch Ultra on a man's wrist, showing the model number
Apple Watch Ultra, after tapping the A model number

Third-party vendors like Amazon and Best Buy can continue to sell through what they have with pulse oximetry. On the morning of January 18, listings are still unmodified, suggesting they all still have the feature.

It's unclear if they will alter listings after that stock runs out to reflect that feature, but it seems likely that they will.tho