macOS 15 IPSW Downloads

Only on devices Apple is still signing it for. macOS 15.6.1 (24G90) is currently signed for 56 models: Mac Studio (M3 Ultra, 2025), Mac Studio (M4 Max, 2025), MacBook Air (13-inch, M4, 2025), MacBook Air (15-inch, M4, 2025), iMac (24-inch, M4, 2024, Four Ports), iMac (24-inch, M4, 2024, Two Ports), Mac mini (M4 Pro, 2024), Mac mini (M4, 2024) and others. Every other macOS 15 build is unsigned and will be rejected at the end of a restore.

Only to a build Apple is signing, and only by erasing: a recovery-mode restore in Finder, the Apple Devices app or iTunes with the IPSW for your exact model. A backup made on a newer version will not restore onto macOS 15, so the backup you need is one taken before you upgraded. Our downgrade guide walks through it.

Apple's servers must approve a firmware before a device will accept it, and Apple only approves the builds it is currently shipping. A signed file can be restored today; an unsigned one is rejected at the end of the process, however you obtained it. Signing status changes without notice, usually within days of a newer release, which is why this catalogue rechecks it automatically.

A Restore erases the device — that is what makes a downgrade possible. An Update with an IPSW keeps your data, but only when moving to a newer version. Either way, make an archived backup on a computer first; an iCloud backup taken on a newer version will not restore onto an older one.