Running a command in macOS Terminal and suddenly hitting a zsh: permission denied wall is one of the most common stumbling blocks for Mac users. Whether you’re editing config files, running scripts, or managing directories, this error stops you cold — but it almost always has a straightforward fix.

In this guide, we’ll break down exactly why “permission denied” appears in Terminal, show you how to check and change file permissions using chmod and chown, and walk through manual fixes step by step — no third-party tools required.

What Is the “Permission Denied” Error in Mac Terminal?

macOS is a Unix-based operating system, which means every file and directory on your Mac carries a set of ownership and permission flags. These flags determine who can read, write to, or execute a given file.

When Terminal displays permission denied, it means the current user account doesn’t have the access level needed to complete that action. The most common reasons are:

• You are not the owner of the file or folder.
• The file is locked or set to read-only.
• You’re running the command without the required superuser (sudo) privileges.
• The command itself is incorrectly formatted.

$ ./myscript.sh
zsh: permission denied: ./myscript.sh

How to Check File Permissions in macOS Terminal

Before changing anything, inspect what permissions are currently set on the file or directory causing the error. Use the ls -l command:

$ ls -l /path/to/your/file

# Example output:
-rw-r--r--  1 yourname  staff  4096 Mar 28 10:00 myfile.txt

The string at the start (-rw-r--r--) tells you everything. Here’s how to read it:

Fix 1: Use chmod to Change File Permissions

The chmod command (change mode) is the primary tool for modifying file permissions in macOS Terminal. The most common fix is granting read, write, and execute permissions to the file owner.

Give Full Permissions to the Owner

$ chmod 755 /path/to/file

# 755 = owner: rwx | group: r-x | others: r-x

Make a Script Executable

If you’re getting permission denied when trying to run a shell script, it likely lacks execute permission. Fix it like this:

$ chmod +x myscript.sh
$ ./myscript.sh

chmod Permission Number Reference

Fix 2: Use chown to Change Directory Ownership

If you own the file but still see permission denied, the issue might be ownership — the file or folder might be registered to a different user. The chown command (change owner) reassigns ownership to your account.

$ chown -R $USER:staff /path/to/directory

# -R applies the change recursively to all files inside

To check your current username, run:

$ whoami
# outputs: yourname

Fix 3: Use sudo for Superuser Access

Some operations — especially those involving system directories — require elevated privileges. Prefix your command with sudo to run it as the superuser:

$ sudo chmod 755 /path/to/restricted/file
# You'll be prompted to enter your Mac login password

Fix 4: Change File Permissions via Finder (No Terminal Needed)

If you’d rather not work inside Terminal, macOS Finder gives you a GUI alternative:

1. Locate the file or folder in Finder.
2. Press Command + I to open the Get Info window.
3. Scroll down to Sharing & Permissions.
4. Click the lock icon and enter your admin password.
5. Change your username’s Privilege from Read only to Read & Write.
6. Close the window and retry your Terminal command.

Fix 5: Check if the File Is Locked

macOS allows files to be “locked” at the system level, which prevents any modifications regardless of permissions. Unlock a file from Terminal:

$ chflags nouchg /path/to/locked/file

# Then verify permissions are correct
$ ls -lO /path/to/locked/file

Or via Finder: Open Get Info (Command + I), and uncheck the Locked checkbox near the top of the window.

Quick Troubleshooting Reference

Frequently Asked Questions