Should you install macOS updates right away?

For most people, the answer depends on which kind of update it is. Updates within the version you already have, the ones that fix bugs and close security holes, are worth installing within a few days of release. A new major version of macOS, the one with a new name that arrives about once a year, can sensibly wait a few weeks if your work depends on particular apps, plugins or hardware.

Either way, back up first. That one habit turns a bad update from a crisis into an inconvenience. The rest of this post covers how to tell the kinds of update apart, how long it makes sense to wait, and how to set your Mac so that the boring part happens on its own.

Not every update is the same

Software Update shows everything in one place, but what it offers falls into a few different groups.

The first two groups change very little about how your Mac looks or works. They exist to fix problems. The third is a different thing: new features, redesigned settings, and changes underneath that apps from other developers have to catch up with.

Why security fixes shouldn't wait

When Apple ships a security update, it publishes notes describing what was fixed. Those notes are public, which means anyone who wants to exploit an unpatched Mac now has a short list of places to look. Now and then the notes also say that Apple is aware of reports that a flaw may already have been exploited. Those are the updates to install the same day.

There is also a quieter reason to keep current. Apple fixes the newest version of macOS first and most completely. Older versions get some security fixes for a while, but Apple has said that not every known issue is addressed in them. Staying on an old version for years means living with a growing list of known holes.

The risk of a minor update going wrong is real but small. Most problems with them are annoyances, like a setting that resets or an app that needs its own update. That trade is almost always worth making.

Why a short wait for big upgrades is reasonable

A major upgrade is where things break. Not usually macOS itself, but the apps and devices around it:

• Apps from smaller developers. They often need a few days or weeks after a new macOS ships to release a compatible version.
• Plugins and extensions. Audio plugins, design tool plugins and browser extensions tend to lag behind the apps they plug into.
• Hardware drivers. Printers, scanners, audio interfaces and docks sometimes need new software from their makers.
• Work software. If your Mac belongs to your employer, IT may hold upgrades back on purpose until they have tested them. Follow their lead.

A reasonable rule is to wait until the first point update of the new version has shipped, which usually takes a few weeks, and until the developers of the apps you rely on say they support it. Most developers post this on their website or in their release notes. If your work runs on two or three critical apps, check those specifically.

If you only use Apple's own apps and a browser, you can upgrade sooner. Apple tests its apps against the new version, and the main risk is getting used to things that moved.

Waiting does not mean skipping. Once the new version has been out a few months and your apps are ready, make the move. Every year you stay behind is another year of fixes you only partly get.

Set up automatic updates

On a Mac with a recent version of macOS:

1. Open System Settings > General > Software Update.
2. Click the round info button beside Automatic updates.
3. Turn on the switches you want. The names vary a little between versions, but you will usually see Download new updates when available, Install macOS updates, Install application updates from the App Store, and Install Security Responses and system files. Some versions also list Check for updates.

For most people, all of them on is the right setting. Security Responses in particular are small and worth having automatically. Install macOS updates is the one to think about: it lets your Mac apply updates within your current version on its own, usually overnight. A new major version is typically offered as a separate upgrade that you choose to start, but read what Software Update says before you click anything.

On the same page you may see a Beta updates option. Leave it off on a Mac you work on. Beta versions are for testing, and they are not where you want your client files.

If you like Terminal, softwareupdate --list shows any pending updates without installing them.

Back up before anything big

Before a major upgrade, and ideally before any update, make sure you have a recent backup. If you use Time Machine, open its menu in the menu bar and choose Back Up Now, then wait for it to finish. If you don't have backups yet, Time Machine needs only a few minutes of setup, plus a long first backup, and few things you can do for your Mac matter more.

A few other things help an upgrade go smoothly:

• Plug in. A laptop should be on its charger for the whole install.
• Leave free space. Upgrades need room on the startup disk to unpack. If storage is tight, clear some first.
• Set aside time. A major upgrade can take a while and restart more than once. Start it at the end of the day, not before a meeting.
• Save and quit. Close apps with unsaved work yourself, so nothing waits on a dialog you never see.

The restart that never happens

A common pattern is the update that downloads, asks for a restart, and then waits. You click Later because you are in the middle of something, and a week goes by. The update is on the Mac but not applied, so neither are its fixes.

The fix is to give restarts a regular slot. A restart once a week is enough for most people, and it gives any waiting update a chance to finish. Notchpals can help with the restart, though not with the update itself: it has no idea whether one is waiting. What its Tech care characters, Gumdrop and Juice, keep track of is uptime. After seven days without a restart, the one in your crew comes out of the notch during the working day (9 AM to 6 PM) and proposes one. Quite often that is the restart a downloaded update was waiting for.

GumdropA week with no restart! Even gumballs need a shake. Restart soon?

If you are mid-sentence, press Later and it asks once more, 20 minutes on. A second Later and it lets the matter drop, which is fine on a busy day but is also exactly how a week becomes a month. If you want to know whether a weekly restart is worth it for you, the post on how often to restart a Mac goes into it.

A simple rule of thumb

• Security Responses: let them install automatically.
• Updates within your version: install within a few days, ideally overnight.
• A new major version: back up, check your critical apps, then upgrade within a few weeks or months, not years.
• Restarts: once a week, so waiting updates actually finish.

None of this needs much attention once automatic updates are on. The only real decision you make each year is when to take the big upgrade, and a backup makes that decision a lot less nerve-racking.