How to Add User to Sudoers on Ubuntu 26.04

Adding a user to sudoers on Ubuntu 26.04 grants that user the ability to execute commands with elevated root privileges using the sudo command. Whether you are setting up a new server, creating accounts for team members, or troubleshooting an access issue, knowing how to sudo add a user on Ubuntu 26.04 is an essential system administration skill. This guide covers every supported method, including the recommended group-based approach and direct sudoers file editing.

Software Requirements

Software Requirements and Linux Command Line Conventions

Category	Requirements, Conventions or Software Version Used
System	Ubuntu 26.04 Resolute Raccoon
Software	sudo 1.9.x (pre-installed), usermod (util-linux)
Other	Privileged access to your Linux system as root or via the sudo command.
Conventions	# – requires given linux commands to be executed with root privileges either directly as a root user or by use of sudo command $ – requires given linux commands to be executed as a regular non-privileged user

TL;DR

Add User to sudo Group on Ubuntu 26.04

The simplest and most recommended way to sudo add a user on Ubuntu 26.04 is to add them to the sudo group. Ubuntu pre-configures this group in /etc/sudoers with full administrative access, so any user who belongs to it automatically gains the ability to run commands as root.

Use the usermod command with the -aG flags. The -a flag appends the user to the group without removing them from any existing groups, and -G specifies the target group:

1. Add the user to the sudo group: Replace linuxconfig with the actual account name you want to grant privileges to.

   # usermod -aG sudo linuxconfig

   This command modifies the user’s group membership in /etc/group. The change takes effect at the user’s next login session.

   IMPORTANT
   The usermod -aG sudo linuxconfig command must be executed with root privileges. Run it either directly as the root user, or prefix it with sudo from an account that has already been assigned to the sudo group: sudo usermod -aG sudo linuxconfig

2. Apply the group change immediately: To avoid logging out, the target user can run newgrp in their existing session to activate the new group membership:

   $ newgrp sudo

   Note that newgrp is not installed by default on Ubuntu 26.04. Install it first with sudo apt install util-linux-extra. Alternatively, simply log out and log back in.

Edit the sudoers File Directly with visudo

An alternative approach is to edit the /etc/sudoers file directly. You should never edit this file with a regular text editor because a syntax error can lock all users out of sudo on the entire system. Instead, always use visudo, which validates the file before saving.

1. Open the sudoers file: Run visudo with root privileges.

   # visudo

   This opens /etc/sudoers in your default editor (typically nano on Ubuntu 26.04).

2. Add a privilege line for the user: Scroll to the end of the file and add the following line, substituting the actual linuxconfig:

   linuxconfig ALL=(ALL:ALL) ALL

   This rule means the user can run any command as any user or group from any host. The format is: user host=(runas_user:runas_group) commands.

3. Save and exit: In nano, press Ctrl+O then Enter to save, followed by Ctrl+X to exit. visudo will validate the syntax before writing the file.

You can also restrict the user to specific commands. For example, to allow a user to only restart a specific service:

linuxconfig ALL=(ALL) /usr/bin/systemctl restart nginx

This is a much safer approach for service accounts or automation users. For a broader look at privilege configuration, the official Ubuntu Sudoers documentation provides an in-depth reference.

Add a Drop-in File to /etc/sudoers.d/

Ubuntu 26.04 includes the /etc/sudoers.d/ directory, which allows you to place individual sudo configuration files rather than editing the main /etc/sudoers file. This approach keeps configurations modular and easier to manage, especially when you want to grant privileges to specific users or groups independently.

1. Create a new drop-in file with visudo: Use the -f flag to specify a new file path. Replace linuxconfig in the filename with the actual account name.

   # visudo -f /etc/sudoers.d/linuxconfig

2. Add the privilege rule: In the editor, add the appropriate rule for the user.

   linuxconfig ALL=(ALL:ALL) ALL

3. Set correct permissions: The file must be owned by root and not world-writable. visudo handles this automatically, but if you copy a file in manually, set permissions explicitly:

   # chmod 0440 /etc/sudoers.d/linuxconfig

When adding users to groups for system administration tasks, the drop-in approach scales well because you can remove a user’s sudo access simply by deleting their file without touching the main configuration.

Verify sudo Access on Ubuntu 26.04

After you sudo add a user on Ubuntu 26.04 using any of the methods above, confirm that the change is working correctly. Switch to the target user account and run a command that requires root access:

$ sudo whoami

If sudo is configured correctly, the output will be:

root

You can also list the user’s effective sudo privileges with:

$ sudo -l

This displays all commands the current user is allowed to run, along with any restrictions. It is a useful diagnostic step when troubleshooting sudo issues.

If the user needs to run sudo commands without entering a password each time, you can configure sudo without a password for that account. Similarly, if you want to understand the full range of what the sudo command can do, reviewing its options is worthwhile.

Remove sudo Privileges from a User

Revoking sudo access is just as important as granting it. The method you use to remove privileges depends on how they were originally granted.

1. Remove from sudo group: Use deluser or gpasswd to remove the user from the sudo group.

   # gpasswd -d linuxconfig sudo

   The change takes effect at the user’s next login.

2. Remove a sudoers.d drop-in file: Simply delete the file you created earlier.

   # rm /etc/sudoers.d/linuxconfig

   This immediately removes the user’s custom sudo rules.

3. Comment out a visudo entry: If the rule is in the main /etc/sudoers file, open it with visudo and prefix the relevant line with a # to disable it.

   # linuxconfig ALL=(ALL:ALL) ALL

To verify the user no longer has sudo access, switch to their account and attempt a privileged command. They should see a permission denied error or be prompted to contact the system administrator.

For additional scenarios involving running sudo without a password, ensure those configurations are also reviewed when revoking access.

Conclusion

This guide covered the primary methods to sudo add a user on Ubuntu 26.04: using the sudo group via usermod, editing the sudoers file directly with visudo, and creating a modular drop-in configuration in /etc/sudoers.d/. For most use cases, the group-based method is the cleanest and easiest to maintain. Direct sudoers entries are best reserved for situations requiring command-specific restrictions. Always verify access after any change and revoke privileges promptly when they are no longer required.

Frequently Asked Questions

1. What is the difference between adding a user to the sudo group vs. editing the sudoers file? Adding a user to the sudo group grants them full root access through Ubuntu’s pre-configured group rule in /etc/sudoers. Editing the sudoers file directly gives you more control, such as restricting which commands the user can run. For general administrative access, the group method is simpler and easier to manage.
2. Do I need to log out after adding a user to the sudo group on Ubuntu 26.04? Yes, group membership changes do not apply to existing sessions automatically. The user must log out and log back in, or use newgrp sudo in their current terminal to activate the new group without a full logout. Note that newgrp requires the util-linux-extra package, installable with sudo apt install util-linux-extra.
3. What happens if I edit /etc/sudoers without using visudo? Editing /etc/sudoers directly with a standard text editor such as nano or vim bypasses syntax validation. A single typo can render sudo completely non-functional for all users, potentially locking you out of root access. Always use visudo, which validates the file before saving and prevents you from writing a broken configuration.
4. How do I check which users have sudo privileges on Ubuntu 26.04? Run grep -Po '^sudo.+:\K.*$' /etc/group to see members of the sudo group. Additionally, review /etc/sudoers and all files in /etc/sudoers.d/ for any user-specific entries that grant elevated access outside of the group.