Big macOS updates always make me nervous. Spotting bricked Macs in forums teaches you to be careful. Apple usually nails these but small disasters happen if you skip the prep steps.
Here's the safe order to update macOS without losing data or breaking apps.
Back up Time Machine first
Always. If anything goes wrong during the update, Time Machine lets you roll back. Skip this step at your own risk.
Connect a Time Machine external drive. Open System Settings > General > Time Machine. If your drive is set up, click Back Up Now.
If you don't have Time Machine, buy a 1TB external drive for $50-80. Set it up. Run a full first backup before updating. Takes a few hours but saves you potentially everything.
Make sure storage is sufficient
Major macOS updates need 20-30 GB of free space temporarily. If your drive is full, the update fails midway. Worse than failing – it can corrupt your existing OS.
Apple Menu > About This Mac > Storage. Make sure you have at least 30 GB free. Clear space if needed before updating.
Confirm your Mac supports the new version
Apple drops support for older Macs with each major release. Before updating, check Apple's compatibility list for the version you're moving to.
If your Mac is on the supported list, you're good. If not, stay on your current version. There's no benefit to forcing newer macOS on unsupported hardware – performance suffers dramatically.
Check critical apps for compatibility
Some pro apps lag behind macOS updates. If you depend on:
- Adobe Creative Cloud apps
- Microsoft Office
- Logic Pro or Pro Tools
- Final Cut Pro
- Specific drivers (printer, scanner, audio interface)
Search the vendor's page for compatibility notes about the new macOS version. Wait if any critical app isn't supported yet. The risk of broken workflows isn't worth being first to update.
Plug into power and use Wi-Fi
For MacBooks, plug in the power adapter. The update can take 30-60 minutes and you don't want the battery dying mid-update.
Connect to reliable Wi-Fi. Better yet, use Ethernet if available. The installer downloads 5-10 GB. Interrupted downloads mean restarting from scratch.
Start the update
System Settings > General > Software Update. Wait for it to check. If an update is available, click Upgrade Now for major version or Update Now for minor.
Accept the license. Enter your password. The download starts. When complete, the Mac restarts and installs.
Don't interrupt. Don't close the lid. Don't touch anything. Let it finish.
After the update finishes
Your Mac restarts to the login screen. Sign in. macOS does some first-run setup like syncing iCloud, installing helper apps, indexing search.
First boot after a major update is slow. The Mac is updating its search index, app caches, and Spotlight. Don't panic if things feel sluggish for the first hour. Performance returns once indexing finishes.
Test critical apps
Open every important app you use daily. Make sure they launch and work. Common issues:
- App needs an update for the new macOS
- Permissions changed and need to be re-granted
- Login items disabled by macOS Sequoia's stricter security
- VPN apps require approval again
- Audio drivers need to be reinstalled
For each issue, the app vendor usually has a guide on their support page. Most issues clear with a quick reinstall or update.
Skip versions you don't need
You don't have to update to every new macOS. The current version (Sequoia for example) gets security patches for 2-3 years even after newer versions release.
If your apps don't support a new version, stay where you are. Wait until they catch up. Apple sometimes pushes prompts to update but you can dismiss them indefinitely.
Rolling back if it broke things
If the new macOS breaks something critical and a fix isn't coming, you can roll back via Time Machine. Restart in Recovery Mode (hold Cmd + R on Intel, hold power button on Apple Silicon).
Pick Restore from Time Machine Backup. Connect your Time Machine drive. Pick the backup from before the update. Mac restores to that exact state.
Anything you did after the failed update is lost. So roll back early if you're going to roll back at all.
Which macOS version are you on and which one are you considering moving to? Tell me and I'll mention any known issues with that jump.