watchOS 5.3.10 (build 16U711) is an official Apple over-the-air update for the Apple Watch Series 3 (38mm), released on 2026-03-24T18:35:23Z. The update package is 480.91 MB. This is a delta (partial) update that requires 5.1.3 already installed. This update is currently signed by Apple, so it can be applied from Settings › General › Software Update.

Payload file: c50665247f06d70fca3f4f68508cd878242b8bb1.zip.