How to lock an app on a Mac with a password, and what works instead

4 October 2026 · 7 min read

macOS does not have a per-app lock. At the time of writing there is no setting that puts a password or Touch ID prompt in front of Mail, Messages or any app you choose, the way an iPhone can. What you can do is lock the whole Mac quickly, use a Screen Time limit as a rough app lock, give other people their own account, or lock the files an app would open rather than the app. Which one fits depends on who you are keeping out.

Start with who you are keeping out

Anyone who walks past while you are away from the desk. Lock the screen. It covers every app at once.
A child or a guest who uses the Mac with your permission. A separate account, or Screen Time.
Someone who uses your account, or knows your login password. A screen lock does nothing here. The answer is locking the files with a different password; Keep files private from someone who knows your Mac password covers that case.

Lock the whole Mac in one keystroke

Control-Command-Q locks the screen immediately. So does Lock Screen in the Apple menu, and a press of the Touch ID button on a MacBook.

For this to mean anything, open System Settings, Lock Screen, and set Require password after screen saver begins or display is turned off to Immediately. Require a password immediately after a Mac sleeps goes through the setting and its gaps.

This is the only built-in method that protects every app, including windows that are already open.

Use Screen Time as a rough app lock

Screen Time is built for limiting a child’s use, but it can put a passcode in front of a single app.

Open System Settings, then Screen Time. Turn on App & Website Activity if it is off.
Turn on Lock Screen Time Settings (Use Screen Time Passcode on earlier versions) and choose a passcode you use nowhere else. On an administrator account, macOS may point out that a passcode works best on a standard account and offer to change yours. Read that dialog rather than clicking through it.
Open App Limits, turn it on, and click Add Limit.
Click the arrow beside a category to open it, and tick the one app you want.
Set the time to 1 minute, every day, and tick Block at end of limit.

After a minute of use each day, the app is covered by a time limit screen and asks for the Screen Time passcode to continue.

Know what this is before you rely on it:

The app works normally for the first minute of every day, and macOS offers one more minute without the passcode. Whatever is on screen can be read in that time.
The limit resets at midnight.
The passcode is four digits.
With Share Across Devices on, the same limit follows the app to your iPhone and iPad.
Nothing is encrypted. The app’s data is still on the disk, readable in Finder and by other apps.

It is a deterrent for children and the casually curious. It is not protection against someone determined.

Give other people their own account

Apps keep mail, messages, browser history and documents separately for each user account. If the other person signs in to their own account, your apps open with their data, not yours.

Open System Settings, Users & Groups, and click Add User to create a Standard account. For occasional visitors, turn on Guest User instead; a guest’s files are deleted when they log out. Fast user switching in Control Center moves between accounts without closing your work.

This is the closest macOS gets to locking all of your apps from one person while they still use the Mac. Standard, admin and guest accounts explains which type to pick.

Locks that already exist inside apps

A few Apple apps have their own locks, and they are worth switching on:

Notes can lock individual notes. See Locked notes on a Mac.
Photos can keep the Hidden and Recently Deleted albums behind Touch ID or your password: Photos, Settings, General.
Safari can lock Private Browsing windows when you are not using them: Safari, Settings, Privacy.
Passwords asks for Touch ID or your password every time it opens.

Some messaging and finance apps from other developers have a passcode or Touch ID lock of their own. Look in the app’s settings for words such as lock, passcode or privacy.

Lock the files instead of the app

Often the app is only a viewer. What is private is the spreadsheet, the scans, the contract or the journal it opens. Lock those, and it stops mattering which app is installed or running.

The built-in way is an encrypted disk image made with Disk Utility: a password-protected container you open when you need it and eject when you are done.

Hushbox does the same job without the container to manage. To be plain about it, it does not lock apps. It locks files and folders where they sit: right-click one in Finder, choose Lock with Hushbox, and it becomes an AES-256 encrypted disk image of the kind Disk Utility makes, in the same folder. It opens with Touch ID or your Hushbox password, and locks again by itself when the screen locks, when the Mac sleeps, or after the idle time you pick. While locked, the contents stay out of Spotlight, Finder Recents and Quick Look previews.

Two honest limits. The name of a locked item still shows in Finder, and other apps’ Open Recent menus may remember file names. And this suits documents you keep in a folder, not an app’s own internal database, such as a mail store or message history, which the app expects to find in the Library every time it starts. For those, a separate user account is the right tool.

Hushbox is $9 once for two Macs, free for 24 hours with every feature, and unlocking stays free after that, so nothing is ever held hostage.

What does not work

Removing the app from the Dock or tucking it in a folder. Spotlight still opens it in two keystrokes.
The Locked checkbox in Finder’s Get Info window. It prevents changes; it does not stop anything being opened.
Renaming the app. It still opens, and updates may stop working.

Questions

Can I lock an app with Touch ID on a Mac? Not in general. Touch ID unlocks the Mac, approves purchases and fills passwords, and it guards the specific features listed above. There is no system switch that adds it to an app of your choice.

What if someone knows my Mac password? Then they can sign in as you, and the screen lock and separate accounts stop helping. A file lock with its own password, different from the login password, is the layer that still holds.

Will a second user account slow the Mac down? Only while that account is logged in with apps running in the background. Log the other account out when it is not needed, and expect its files to take some disk space.