Knowing how to install an operating system from scratch is still valuable, but Ubuntu 20.04 LTS now needs some context. Ubuntu 20.04 “Focal Fossa” is a legacy release in 2026. It still installs and runs, but it should not be the default choice for a new desktop simply because an older tutorial happens to use it.
This guide is for people who need to reproduce a Focal environment, maintain older software, build a compatibility VM, or recover a system that still depends on Ubuntu 20.04. If you simply want Ubuntu on a new computer today, download the current release from the official Ubuntu Desktop site.
Ubuntu 20.04 support status in 2026
Ubuntu 20.04 LTS was released on April 23, 2020 and reached the end of standard security maintenance on May 31, 2025.
Canonical still offers extended coverage through Ubuntu Pro and Expanded Security Maintenance (ESM). Ubuntu 20.04 can receive extended security maintenance through 2030, and Canonical also offers a Legacy add-on for organizations that need to keep the release in service even longer.
Ubuntu Pro is available at no cost for personal use and certain small deployments of up to five machines. Larger or commercial deployments should review Canonical’s current subscription terms rather than assuming the personal-use conditions apply.
For a new installation, use Ubuntu 26.04.1 LTS
Ubuntu 26.04 LTS is the current long-term support generation. Canonical provides five years of standard security maintenance for that release, through 2031, with longer coverage available through Ubuntu Pro.
That makes the decision straightforward: install 20.04 only when you have a specific compatibility reason. Otherwise, a current LTS gives you newer kernels, broader hardware support, newer application stacks, and a much longer standard support window.
Use the Ubuntu 20.04.6 LTS image
If you specifically need Focal Fossa, use the final point-release installer for the series: Ubuntu 20.04.6 LTS.
Canonical still publishes the AMD64 desktop ISO and its verification files at the official Ubuntu 20.04.6 release archive.
The same directory includes SHA256SUMS and its signature. Verifying the ISO checksum is a good habit, especially when the image has been stored for a long time or copied through an internal file repository.
Back up the computer before a clean install
A clean installation can erase an entire disk. Back up documents, SSH keys, certificates, browser profiles, configuration files, encryption recovery material, and anything else you cannot afford to lose.
If the machine runs specialized software, also record package names, application versions, license information, and any external repositories that will be needed after reinstalling.
Make sure you have the correct architecture
The Ubuntu 20.04.6 desktop image currently published in the standard Focal release directory is intended for AMD64/x86-64 PCs, which covers conventional 64-bit Intel and AMD systems.
Do not assume that the same image is appropriate for an Arm system. Architecture matters whether Ubuntu is being installed on physical hardware or inside a VM.
If you are installing Ubuntu in VirtualBox, start with our guide to creating a GNU/Linux virtual machine in VirtualBox 7.2.
Create the installation media
On physical hardware, write the ISO to a USB drive with a trusted imaging tool and boot the computer from that device using its firmware boot menu. In a virtual machine, attach the ISO to the virtual optical drive.
When the hardware supports it, installing in UEFI mode is usually preferable. Ubuntu 20.04 also supports legacy BIOS, but UEFI with GPT better matches a modern system.
You do not need to disconnect the Internet
The original version of this article recommended installing Ubuntu offline to avoid update failures. That is no longer good general advice.
You can install Ubuntu with an Internet connection and let the installer obtain updates or additional software when appropriate. If the connection is unreliable, you can also finish the installation first and update immediately afterward. There is no general security or reliability benefit to intentionally keeping a new Ubuntu installation offline during setup.
Try Ubuntu or install it directly
The Ubuntu Desktop image includes a live environment. You can boot into Try Ubuntu without modifying the disk, or start the installer immediately.
The live session is useful for checking Wi-Fi, audio, graphics, keyboard layout, and other hardware before committing to an installation. In a VM, it is also a convenient way to verify that display and input settings are usable.
Choose language and keyboard layout
The installer asks for the interface language and keyboard layout. Use the test field to make sure punctuation and special characters appear where you expect them, particularly on non-US keyboards.
Normal installation, minimal installation, and third-party software
Ubuntu 20.04 offers a normal desktop installation and a smaller minimal installation. The normal option installs the typical desktop application set. Minimal installation is useful for a VM or a system where you prefer to add applications individually.
The third-party software option can add proprietary drivers and media components needed by some physical systems. It is often useful for NVIDIA graphics or certain wireless adapters. In a VirtualBox guest, it may provide little additional value because the VM sees VirtualBox virtual hardware rather than the host’s physical GPU and Wi-Fi adapter directly.
The most important screen: storage
Erase disk and install Ubuntu means exactly what it says: the selected disk will be repartitioned for Ubuntu.
Inside a VM with a virtual disk created only for Ubuntu, that is usually the simplest option. On a physical computer, stop and verify the disk carefully if it contains files, another operating system, or an OEM recovery partition.
The manual partitioning option is appropriate for dual boot, custom mount points, preserving existing partitions, or more advanced storage designs. It is also where mistakes can be most destructive, so do not delete or format a partition unless you know what it contains.
LVM and disk encryption
Ubuntu 20.04 can use LVM and full-disk encryption in supported installation flows. Encryption is particularly valuable on laptops or systems holding sensitive information.
Keep the encryption passphrase or recovery information in a safe place. Encryption protects data from unauthorized access, but it also means lost credentials can make your own data unrecoverable.
Time zone and user account
Choose the correct time zone and create the primary user account. Use a long, unique password or passphrase rather than relying on a mechanical recipe such as “eight characters, one uppercase letter, and one symbol.”
The first user created during Ubuntu Desktop installation normally receives administrative privileges through sudo, so protect that account accordingly.
Finish installation and reboot
Ubuntu copies the system files, installs packages, configures the boot loader, and then asks you to restart.
On physical hardware, remove the USB media when prompted. In a VM, detach the ISO so the next boot starts from the installed virtual disk rather than returning to the installer.
Update immediately after the first boot
This is particularly important with Ubuntu 20.04 in 2026 because the 20.04.6 desktop ISO predates many later security updates.
Open a terminal and run:
sudo apt update
sudo apt full-upgradeRestart the system if the kernel or other core components were updated.
Check Ubuntu Pro and ESM status
If the system will remain on Ubuntu 20.04, check its actual security coverage rather than assuming that “LTS” still means standard updates are arriving.
pro status
pro security-statusIf the machine is eligible and you have an Ubuntu Pro entitlement, follow Canonical’s Ubuntu Pro documentation to enable the appropriate ESM services.
The distinction matters: a machine can continue booting and running normally while no longer receiving standard security patches.
Drivers and firmware on physical hardware
On a physical Ubuntu desktop, review Software & Updates → Additional Drivers after installation. Some NVIDIA GPUs, wireless adapters, and other devices may have recommended proprietary drivers.
In VirtualBox, guest integration is handled through VirtualBox Guest Additions instead. Keep the guest kernel and the integration components in a compatible state.
Ubuntu 20.04 inside VirtualBox
After the guest is updated, install the appropriate Guest Additions components if you need dynamic display resizing, shared clipboard, shared folders, or tighter mouse integration.
Our VirtualBox Linux VM guide covers current recommendations for CPU, memory, storage, networking, and UEFI.
Should an existing Ubuntu 20.04 system be upgraded?
In most cases, yes. If a specific application, hardware dependency, or validated production environment does not require Focal, moving to a supported LTS reduces security and maintenance debt.
Canonical supports LTS upgrades sequentially. An in-place upgrade from Ubuntu 20.04 moves first to 22.04 LTS. From there, the supported path continues to 24.04 LTS and then onward to the next LTS when that upgrade path is enabled. Do not try to skip multiple LTS generations in a single do-release-upgrade operation.
Before each major release upgrade, make a verified backup, fully update the current release, remove or review third-party repositories, and read the release notes for the target version.
Ubuntu 20.04 or Ubuntu 26.04.1?
For a new workstation, general-purpose desktop, or VM with no legacy requirement, choose Ubuntu 26.04.1 LTS. It provides a current kernel, newer hardware enablement, newer user-space software, and a much longer standard maintenance window.
Use Ubuntu 20.04 when you need to reproduce an existing environment, validate older applications, or maintain a system that is deliberately covered by Ubuntu Pro/ESM while a migration plan is completed.
