Apple has officially stopped signing iOS 18.5 following the public release of iOS 18.6. This change means users can no longer downgrade to iOS 18.5 through Finder or iTunes after updating to the latest version. Once Apple stops signing a firmware version, it becomes inaccessible for installation, regardless of whether it was previously downloaded.
The release of iOS 18.6 was a small but important update that focused on resolving bugs, improving performance, and preparing iPhones for future enhancements. While it did not introduce any significant user-facing features, it is a critical step in Apple’s development cycle as the company prepares for the larger iOS 26 update expected later this year. Apple typically follows this pattern in the months leading up to a major software release, using point updates like iOS 18.6 to finalize system behavior, test compatibility, and improve background frameworks.
Now that Apple has stopped signing iOS 18.5, users who may encounter issues with iOS 18.6 no longer have the option to roll back to the previous version. This can be frustrating for some, especially those who rely on jailbreaks, third-party tools, or specific app compatibility that may not yet be fully stable under the latest software. However, Apple’s strict control over signing is designed to ensure the ecosystem remains unified and secure. By limiting which versions can be restored, Apple reduces fragmentation across devices and ensures that developers are building and testing against the same baseline.
For everyday users, the impact of Apple stopping signing iOS 18.5 is mostly behind the scenes. Devices running iOS 18.6 will continue to receive support, and users are not prompted to downgrade in normal usage. Still, this change matters for those who may have held off on updating or who use advanced tools that depend on specific firmware versions.
In general, Apple’s firmware signing status is a useful indicator of which software versions are officially supported. Once a version is unsigned, it is effectively deprecated. This approach helps Apple accelerate adoption of security fixes and performance updates across millions of devices. It also discourages the use of outdated software that may have known vulnerabilities or lack optimizations introduced in later versions.
