How to Update macOS: Complete Guide for Every Mac

We’ve seen too many people postpone macOS updates for months because they’re worried something will break. In practice, Apple Silicon Macs handle updates remarkably well — and the security patches alone make updating worth it. Skipping updates doesn’t protect your workflow. It exposes it.

Here’s the complete process, from checking compatibility to fixing a stuck update.

Check Your Current macOS Version

Before anything else, know where you stand.

1. Click the Apple menu () in the top-left corner
2. Select About This Mac
3. Your macOS version and build number appear at the top

You’ll see something like “macOS Tahoe 17.3” or “macOS Sequoia 15.4.” Note the version number — you’ll need it to check compatibility for the next major release.

How to Update macOS

The actual update process is straightforward:

1. Click the Apple menu → System Settings
2. Go to General → Software Update
3. Your Mac checks Apple’s servers for available updates
4. If an update is available, click Update Now (for minor updates) or Upgrade Now (for major version upgrades)
5. Agree to the terms
6. Your Mac downloads the update, then restarts to install

Minor updates (like 17.3 to 17.4) usually take 15-30 minutes total. Major version upgrades (like 16.x to 17.0) can take 45 minutes to over an hour depending on your Mac and storage situation.

Keep your Mac plugged in during the update. On a MacBook, the installer won’t start if your battery is below 50%.

Check Compatibility First

Not every Mac supports every macOS version. Apple drops support for older hardware with each major release.

To check if your Mac supports the latest macOS:

1. Go to Apple’s website and find the compatibility list for the new version
2. Or just try — System Settings → Software Update will only show you updates your Mac can actually run

As a general rule, Apple Silicon Macs (M1 and later) will be supported for many years. Intel Macs are the ones getting dropped. If you’re on an M1 or newer, you’re fine for the foreseeable future.

Back Up with Time Machine First

This is the step everyone skips, and the step that saves you when things go wrong.

1. Connect an external drive (USB-C or Thunderbolt)
2. Go to System Settings → General → Time Machine
3. Click Add Backup Disk and select your drive
4. Wait for the initial backup to complete

A full backup of a 256GB drive takes roughly 30-60 minutes on a fast external SSD. Once the backup finishes, you can update with confidence. If anything goes sideways, you can restore your entire system from this backup.

No external drive? At minimum, make sure your important files are in iCloud Drive or another cloud service. It’s not as comprehensive as Time Machine, but it’s better than nothing.

What to Do If the Update Gets Stuck

It happens. The progress bar sits at “About 2 minutes remaining” for 45 minutes. Here’s what to actually do:

Wait longer than you think. Seriously. Some updates look frozen but are actually working. The progress bar is notoriously inaccurate. Give it at least an hour before intervening.

Check if it’s truly stuck. Press Cmd+L during installation to see a detailed log. If log entries are still appearing, the update is progressing. Leave it alone.

If genuinely frozen (no log activity for 30+ minutes):

1. Press and hold the power button for 10 seconds to force shutdown
2. Wait 10 seconds
3. Press the power button to restart
4. Your Mac should either resume the update or boot to your previous macOS version

If it boots to a blank screen or recovery:

1. On Apple Silicon: Hold the power button until you see “Loading startup options”
2. Select Options → Continue to enter macOS Recovery
3. Try reinstalling macOS from Recovery
4. If that fails, restore from your Time Machine backup (this is why we backed up)

How to Do a Clean Install

Sometimes you want a fresh start. Maybe your Mac has accumulated years of junk, or you’re selling it.

1. Back up everything important
2. Restart and hold the power button (Apple Silicon) until Recovery appears
3. Select Disk Utility → select your startup disk → Erase
4. Choose APFS format
5. Close Disk Utility
6. Select Reinstall macOS from the Recovery menu
7. Follow the prompts

A clean install gives you a fresh system with zero leftover files. It takes longer (you’ll need to reinstall all your apps), but the result is a Mac that feels brand new.

Set Up Automatic Updates

If you’d rather not think about updates at all:

1. System Settings → General → Software Update
2. Click the info (i) button next to “Automatic Updates”
3. Enable all options:
   • Check for updates: On
   • Download new updates when available: On
   • Install macOS updates: On
   • Install Security Responses and system files: On

We recommend keeping at least the security responses enabled. These are small, fast patches that don’t require a restart and fix critical vulnerabilities. There’s no good reason to delay them.

For major version upgrades, we’d suggest waiting 2-3 weeks after release before installing. Let early adopters find the bugs first. Minor point updates (x.1, x.2) are generally safe to install right away.

How Long Do Updates Take?

Rough estimates based on our experience:

• Security Response: 2-5 minutes, no restart
• Minor update (e.g., 17.3 → 17.4): 15-30 minutes
• Major upgrade (e.g., 16 → 17): 45-90 minutes
• Clean install: 30-60 minutes (plus app reinstallation time)

These times assume an Apple Silicon Mac with a decent internet connection. Intel Macs run noticeably slower during installation. And if you’re low on storage (less than 20GB free), the update will take longer because macOS needs to shuffle files around.

Free up storage before updating if you’re tight on space. The installer needs roughly 12-15GB of working room for minor updates, and up to 35GB for major upgrades.