watchOS 6.3.1

watchOS

Version

6.3.1

Build ID

17U224

File Size

675.33 MB

Release Date

2026-02-02T18:44:40Z

Update Type

Normal release

Delta update - requires 6.0.1 installed first.

Download OTA

Looking for beta firmware? View beta builds for Apple Watch Series 4 (44mm, LTE) →

About This Update

watchOS 6.3.1 (build 17U224) is an official Apple over-the-air update for the Apple Watch Series 4 (44mm, LTE), released on 2026-02-02T18:44:40Z. The update package is 675.33 MB. This is a delta (partial) update that requires 6.0.1 to already be installed on the device - it cannot be applied from scratch. This update is currently signed by Apple, so it can be applied directly from Settings › General › Software Update.

The OTA payload file is 4337862e3bf469436ab4465fe5e564190efe82f5.zip.

Direct URL

https://updates.cdn-apple.com/2025FallFCS/patches/047-32167/B4E1D322-0BC2-40CD-90AD-D8CEFE2FC512/com_apple_MobileAsset_SoftwareUpdate/4337862e3bf469436ab4465fe5e564190efe82f5.zip