macOS 26.6 Developer Preview Beta 4 Lands for Mac Testers
Apple rolled out macOS 26.6 Developer Preview Beta 4 to enrolled developers on Tuesday, exactly one week after the previous build. The update carries build number 25G5057c.
The cadence matches Apple’s usual minor-update rhythm — Beta 3 arrived on June 30, Beta 2 on June 16, and the first Beta on May 27. A mid-cycle refinement release rather than a feature-heavy overhaul, macOS 26.6 sits between last fall’s macOS 26 launch and the upcoming macOS 27 major update already in developer testing.
Apple hasn’t published release notes for Beta 4 yet — detailed changelogs typically surface after the initial rollout window closes. Given the incremental version number, expect the focus to be on stability fixes and under-the-hood polish rather than interface changes.
For developers enrolled in the Apple Developer Program, the update is available through System Settings > General > Software Update. Public beta testers need to register for the Apple Beta Software Program first, then enable beta updates under the same menu path.
The 26.6 release cycle is tracking roughly weekly, suggesting a release candidate could arrive within the next few weeks. A public launch would then follow shortly after. Meanwhile, macOS 27 — the next major version — continues its own beta testing cycle with a different set of features aimed at the fall release window.
Recent milestones in the macOS 26.x release history:
| Date | Release |
|---|---|
| June 30, 2026 | macOS 26.6 Beta 3 (25G5052e) |
| June 30, 2026 | macOS 26.5.2 (25F84) |
| June 16, 2026 | macOS 26.6 Beta 2 (25G5043d) |
| June 2, 2026 | macOS 26.5.1 (25F80) |
| May 27, 2026 | macOS 26.6 Beta 1 (25G5028f) |
| May 12, 2026 | macOS 26.5 (25F71) |
| March 25, 2026 | macOS 26.4 (25E246) |
| September 16, 2025 | macOS 26 (25A354) |