How to Install / Upgrade: Apple rolls out Release Candidates for macOS Tahoe 26.7 and macOS Sequoia 15.8

What happened

Apple rolls out Release Candidates for macOS Tahoe 26.7 and macOS Sequoia 15.8

Apple released the first Release Candidates for macOS Tahoe 26.7 and macOS Sequoia 15.8 on the same day it pushed macOS 27 developer beta 6. A Release Candidate is the build Apple intends to ship publicly if no blocking issues surface, so what you install today is very likely what everyone will get when the update goes live to the general public.

If you are running either macOS Tahoe 26 or macOS Sequoia 15, this guide walks you through what arrived, what changed for developers building on these platforms, how to get the update onto your machine right now, and what to keep an eye on before and after you install.

How it works

What shipped

Apple simultaneously released two separate Release Candidates. The first is macOS Tahoe 26.7, a point update to the macOS Tahoe 26 line. The second is macOS Sequoia 15.8, a point update to the macOS Sequoia 15 line. Both are being released as Release Candidates, meaning they have cleared Apple's internal quality bar and are being handed to registered developers and public beta participants for final real-world validation. These are not feature releases. Point updates at this stage of a software cycle carry security patches, reliability improvements, and targeted bug fixes rather than headline additions.

What changed for builders

Why it matters

Developers registered in the Apple Developer Program can install these Release Candidates today through Software Update on enrolled machines. Because these builds represent Apple's release-ready state, they are suitable for testing your apps against the final shipping environment without waiting for the public release. If your app targets any APIs introduced earlier in the Tahoe 26 or Sequoia 15 cycle, this is the moment to verify that nothing broke in the final pass. Apple typically does not introduce new API surface in a point-release RC, so your focus should be on regression testing rather than adopting anything new. If you maintain a build pipeline that signs and notarizes apps, run a full submission test against one of these builds before the public release lands, because any last-minute changes to the notarization service or system frameworks would show up now rather than as a surprise after shipping day.

How to install or upgrade

Who is affected

On a Mac running macOS Tahoe 26 or macOS Sequoia 15 that is enrolled in the developer or public beta program, open System Settings, select General, and then select Software Update. The Release Candidate should appear there automatically. If it does not appear immediately, wait a few minutes and click the refresh indicator, because Apple staggers the rollout across servers. Once the update appears, click Update Now and follow the on-screen prompts. Your Mac will download the installer, restart into a recovery-like environment to apply the update, and restart again into the finished system. Keep the machine plugged into power throughout this process. The download size varies depending on which build you are currently running, and machines already on a recent beta build of the same version will receive a smaller delta update rather than a full installer. If you want to do a clean install instead of upgrading in place, download the full installer from the Apple Developer portal under the downloads section for the relevant macOS version, then use it to create a bootable installer or upgrade directly from the file.

Gotchas and compatibility

Release Candidates carry the same compatibility caveats as any pre-release build. Third-party kernel extensions, security tools, and certain virtualization products sometimes lag behind OS updates, so check with vendors before upgrading a machine you depend on daily. If you rely on any developer tools tied to specific Xcode versions, confirm that your current Xcode version supports the RC before upgrading the host OS. Machines enrolled in the developer beta program receive these RCs automatically in the Software Update queue, but if your enrollment lapsed or your Apple ID is not attached to an active developer account, you may only see the update after it goes public. Do not attempt to sideload an RC on a machine not already running the matching major version, as the delta updater will reject the package. Back up with Time Machine or your preferred backup tool before installing any Release Candidate, even one as stable as an RC, because unexpected issues can still occur on specific hardware configurations.

What to watch next

What to watch next

Keep an eye on the Apple Security Updates page, which Apple typically publishes alongside or shortly after a public release, listing the CVEs addressed in each build. If no blocking issues emerge from RC testing, the public release of both macOS Tahoe 26.7 and macOS Sequoia 15.8 should follow within days. Watch 9to5Mac and the Apple developer forums for reports of any regressions that surface during this RC window, particularly around system integrity, app notarization, or known bug fixes that were specifically called out as targets for these updates.