Apple has just made the fourth Release Candidates (RCs) of macOS Tahoe 26.7 and macOS Sequoia 15.8 available to both developers and public beta testers following its “Surprise and Shine” event on September 9, 2026. The builds—25G229 for Tahoe 26.7 and 24H23 for Sequoia 15.8—don’t introduce major new features, but instead focus on polishing the systems through bug fixes and performance tweaks. (Exact build numbers: Tahoe 26.7 RC 4 is 25G229; Sequoia 15.8 RC 4 is 24H23.)
What’s Changing (And What Isn’t)
These new RCs carry forward the cleanup work Apple has been doing: security improvements, optimized performance, and resolving glitches. Tahoe 26.7, a macOS release that already has strong foundational features, receives mostly behind-the-scenes refinement. Sequoia 15.8 follows the same path—minor improvements rather than headline features.
Security has been a particular focal point in recent months. Apple’s investment in AI-assisted tools has enabled quicker identification and patching of vulnerabilities. This effort shines through in both Tahoe 26.7 and Sequoia 15.8 RCs, which include recently developed fixes that users are advised to install once the public versions roll out.
When You’ll Get the Update
These fourth RCs are live now for those in Apple’s developer or public beta programs. For users who do not participate in beta testing, the finalized versions are expected to arrive in the coming days—likely as free system updates that provide smoother, more secure Mac experiences without cost.
For current users, updating is fairly simple. If your Mac is running either beta version, you can trigger the update via **System Settings → Software Update**, selecting the latest RC build. If your device is not enrolled, Apple will offer the non-beta release once it’s officially pushed to broader users.
Here are the build numbers again for clarity: macOS Tahoe 26.7 RC 4 – build 25G229, macOS Sequoia 15.8 RC 4 – build 24H23.
The public versions are expected to ship shortly on both platforms, mirror light weight updates that don’t change major features, but bring improved security and performance. The timing suggests Apple is aiming for a smooth transition ahead of a wider rollout.
Why This Matters:
These RC releases are important because they represent the final stabilization phase before Apple drops updates to all users. Any latent bugs, performance degradation, or security holes are likely to be addressed now rather than post-release. Even without new features, this kind of update maintains overall system health.
What to Watch For: Users should expect modest improvements—faster app launches, fewer glitches, better battery life or system responsiveness. Developers should watch release notes closely for security patches that may affect third-party apps. And for regular users, checking for the update soon is wise, especially if you’re security-conscious.
