How to Add a User to Sudoers in Ubuntu

1Add User to the sudo Group (Easiest Way)

To add a user to sudoers the easiest way, you place the user into the built-in sudo group using a single terminal command. Ubuntu’s default sudoers file already contains a rule that gives every member of this group full administrator rights. The user can install software and manage system files, and you don’t have to write any custom configuration rules.

1. Open the terminal, either from the app menu or with the Ctrl+Alt+T shortcut. Make sure you are signed in as an account that already has sudo access.
2. Run the command below, replacing username with the actual user’s name. Ubuntu asks for your own password, not the target user’s. Nothing appears on screen while you type it. That is normal.

sudo usermod -aG sudo username

If the command succeeds, it prints nothing and returns you to the prompt. An error that says the user does not exist usually means a typo in the account name.

3. Have the target user log out and log back in. Group membership is read when a session starts, so a session that was already open will not see the change. If you don’t want to log out, start a new login shell (a command-line session) with the command below to refresh permissions. This only affects that one terminal window.

su - username

To undo the change later, remove the account from the sudo group again. The user then goes back to being a standard account after their next login.

Check the User’s Groups

Before you rely on the new access, check that the account really is in the group. To confirm membership within the sudo group, run this command:

groups username

The target user's name should appear in the resulting output. If it doesn't, the previous step did not work. Check the spelling of the user name and run it again.

Test sudo Access

Membership in the group is not the same as a working sudo. Test it from the account itself.

1. Switch to the target account, or log in as that user.
2. Run the command below.
3. Enter the user's own password when asked.

sudo whoami

A password prompt followed by root output confirms that sudo privileges are working. If you see a message saying the user is not in the sudoers file, the user has not logged out and back in yet, or the group change did not apply.

2Give User Custom sudo Permissions (Using sudoers File)

The sudo group gives all-or-nothing access. If you want to limit a user to certain commands, you have to edit the /etc/sudoers file directly. Rules in that file let you set exactly which commands a user may run, and as which account.

This utility checks for syntax mistakes before saving, which prevents a broken configuration. A single typo in the sudoers file can stop sudo from working for everyone, and that can leave you with no easy way to fix it.

Open sudoers File Safely

You open the sudoers file safely in Ubuntu by running the visudo command in your terminal rather than opening the file in a standard text editor. This built-in tool checks your syntax for errors before saving, which prevents you from accidentally locking yourself out of administrator access. You need to run it with sudo, because only administrators can edit the file.

sudo visudo

This command launches the sudoers configuration inside the default editor. On most Ubuntu installs that is nano. Save and exit as you normally would in that editor. If visudo finds an error when you save, it tells you and asks what to do. Choose the option to go back and edit the file again rather than saving the broken version.

If you prefer the nano text editor, run this command instead to use it for that one session:

Granting full sudo access allows execution of any command with administrator rights. Sudo permissions derive from rules added to the special 'sudoers' file for targeted accounts. Executing the 'sudo' command enables powerful system actions once configuration completes.

The target account gains the ability to execute any command as the superuser via the `sudo` command. System authentication prompts for password verification during command execution as a core security measure.

Allow User to Run sudo Without Password

You allow a user to run sudo without a password in Ubuntu by adding a specific rule to the /etc/sudoers configuration file. Open the file with visudo, as described above, and never with a plain text editor. This setup lets the user run administrative commands immediately without typing a password every time. It also reduces your system security, because anyone who gets at that session or account gets full administrator access with no further check.

Reserve this permission exclusively for automated tasks like scripts running on Ubuntu 22.04.

username ALL=(ALL:ALL) NOPASSWD: /bin/mkdir, /bin/rmdir

If you want to keep the convenience but still demand a password for the riskiest tools, you can add rules that enforce passwords for targeted utilities like apt and systemctl. The example below shows the rules you need:

The `/etc/sudoers.d` folder in Ubuntu manages user permissions for running commands as administrator. Separate configuration files created inside `/etc/sudoers.d` replace direct edits to the main `/etc/sudoers` file. This structural method groups permissions, clarifying individual user capabilities.

Editing the main sudoers file is not the only way to do this. A cleaner option is to give each user a dedicated file, so your changes stay separate from the stock configuration and are easy to remove later. To create a dedicated user file, run:

sudo visudo -f /etc/sudoers.d/username

Add your custom rules to the new file. The syntax must match this example:

username ALL=(ALL:ALL) NOPASSWD:ALL

Tip: File names must not contain dots (.) or end in a tilde (~). Sudo silently skips files with names like that, so your rules will have no effect and you will get no error message. To undo a rule, delete or rename its file.

See What sudo Permissions a User Has

After any change, check what a user is actually allowed to do. To audit permitted commands for a specific user, run this command:

sudo -l -U username

The output lists the commands the audited account may run with sudo, and any restrictions that apply. If the list is shorter or longer than you expected, review the rules you added and check the file name for a stray dot or tilde.

Summary

• Easy method: Add users to the sudo group to give full sudo access. The user must log out and back in before it takes effect.
• Control access: Edit the sudoers file or add files in /etc/sudoers.d for custom permissions, such as limiting a user to certain commands.
• Always use visudo: It checks syntax before saving and prevents mistakes that could lock you out.
• Be careful with passwordless sudo: It can make your system less safe, so use it only where you really need it.
• Check sudo permissions regularly: Use sudo -l -U username to verify what each user can run.

Managing sudo permissions in Ubuntu involves adding users to the sudo group for quick administrative access or editing the sudoers file for custom rules. Always use visudo to prevent syntax mistakes, keep passwordless access to a minimum, and check user permissions regularly with the command line.