Several People Share One Mac. How Do You Keep Photos Private?

The situation

One laptop on the kitchen table. Children do homework on it, a partner checks email, and your photos sit in the same Photos library that everyone opens.

This page is about protecting your own files and photos. The built-in macOS tools cover most of it. The gaps are specific, and you can test each one in a few minutes.

What actually protects you

1. Give each person an account

   In System Settings > Users & Groups, click Add User for each person. Apple says standard users can install apps and change their own settings, but cannot add users or change other users' settings. Standard accounts cannot read each other's home folders.

2. Do not share one login

   If everyone uses your account, nothing else on this list works.

3. Limit administrators

   Apple says an administrator can add and manage other users, install apps and change settings. Make as few people administrators as you can.

4. Lock the screen

   Press ⌃⌘Q when you walk away. Apple lists Control-Command-Q as the shortcut that locks your screen. In System Settings > Lock Screen, set how long the Mac can sit idle before it asks for a password.

5. Turn on FileVault

   It protects the Mac if it is lost. Apple says other users' data is encrypted too, and each person unlocks the disk with their own login password. See FileVault vs a vault.

6. Use Guest User for visitors

   Turn on Guest User in Users & Groups so visitors never need your login. Apple says a guest's files sit in a temporary folder that is deleted when the guest logs out, and with FileVault on a guest cannot reach your encrypted disk.

What the built-in setup does not cover

• The Public and Shared folders. Apple says all users of the Mac can read items there. Keep private files out of them.
• An open session. If you are logged in and walk away, whoever sits down sees what you see. The screen lock only helps if you use it.
• Administrators. An administrator can change permissions, so a second administrator is a second person with wide reach.
• Your Apple Account. Apple says iCloud Photos shows the same library on every device signed in to the same Apple Account. Do not sign other people in to yours.
• Backups. Apple says anyone who gets an unencrypted Time Machine backup disk can read what is on it. See how to encrypt a Time Machine backup.

How to test it

1. Sign in as another user, open Finder and try to reach your Documents folder. If anything opens, fix the permissions before you rely on this setup.
2. Lock the screen with ⌃⌘Q, wait, then wake the Mac. It must ask for a password.
3. Open Photos in each account. Each should show its own library.
4. Log in as Guest, try your folders, then log out. Check that nothing the guest made remains.
5. Open System Settings > Privacy & Security > FileVault and confirm it is on.

A five-item checklist

• Each person has their own account.
• Screen lock needs a password immediately.
• FileVault is on.
• Sensitive files sit in an encrypted container or vault, not in Downloads.
• You eject or lock the container when you finish.

Where a vault fits

If you are logged in and step away, an open session shows your files. Hidden Folder keeps chosen files in an encrypted vault that locks on sleep, on screen lock and after idle time. Hidden vaults mean the app itself does not reveal that a second vault exists. A vault does not replace separate accounts. While it is unlocked, anyone at your open session sees what you see, so lock it with ⌘L first.