To dual boot Linux and Windows, keep Windows installed, create unused disk space for Linux, then install Linux into that space without deleting the Windows partitions. At startup, you choose which operating system to run. Each runs directly on your hardware, rather than inside the other.
The installation itself is usually straightforward. Preparing Windows, handling encryption and checking the installer’s partition changes deserve more attention. A wrong desktop preference is easy to fix. Formatting the wrong partition is rather less forgiving.
This guide covers a typical Intel or AMD PC with Windows already installed, UEFI firmware and a GPT disk. Ubuntu and Linux Mint provide useful installer examples, though wording varies between distributions. For the broader installation process, see how to install Linux on your computer. ARM laptops, unusual RAID arrangements and older Legacy BIOS installations need instructions matched to their hardware.
Decide Whether Dual Boot Fits Your Needs
Dual boot makes sense when you want Linux as a full desktop but still need Windows for an application, game or device. You might use Linux for development and everyday work, then restart into Windows for software that has no suitable Linux version.
The cost is inconvenience and divided storage. You cannot keep both desktops running at once, and switching means saving your work and restarting. Each operating system also needs its own updates, applications and maintenance.
If your aim is simply to learn Linux or run occasional Linux tools, a virtual machine may avoid partition changes altogether. Our guide to running virtual machines with KVM and QEMU covers that approach from a Linux host.
Choose your distribution before changing the disk. Installer behaviour, encryption options and Secure Boot support differ. If that decision is still open, start with how to choose a Linux distribution, rather than choosing whichever ISO happens to finish downloading first.
Step 1: Back Up Windows and Prepare Recovery Access
Make a backup you can actually restore
Copy irreplaceable files to storage outside the computer. Include documents, photographs, local email archives, browser data that is not synchronised, project folders and application settings you need. Open a selection of copied files to check that the backup works.
For a computer you rely on, consider a full disk image as well. A file backup protects your documents; a disk image can preserve the operating system, applications and partition layout. Check your backup tool’s restoration procedure and prepare any rescue media it requires.
Create Windows recovery or installation media on a separate USB drive. Keep another device available for reading instructions if this PC stops booting. Once the backup is complete, disconnect its external drive before installing Linux so it cannot become an accidental installation target.
After Linux is installed, it will need its own backup plan. The distinction between personal file backups, system snapshots and recovery media is covered in backing up and restoring your Linux desktop.
Save the BitLocker recovery key
Check whether Windows uses BitLocker or Device Encryption, even if you do not remember enabling either. Search Windows Settings for encryption, or open Manage BitLocker where that control is available.
Before changing firmware settings or installing another bootloader, save the recovery key somewhere accessible without this computer. A startup security change can cause Windows to request it. The recovery key is a 48 digit number, not your Windows password or PIN; Microsoft’s BitLocker recovery instructions cover account, organisation and offline recovery locations.
Check that the saved key belongs to this device. If the computer is managed by an employer or school, obtain permission before changing encryption, partitions or firmware settings.
Check whether the installer requires decryption
Suspending BitLocker protection and turning BitLocker off are different operations. Suspension leaves the drive encrypted. Turning it off decrypts the drive.
Do not assume suspension satisfies an installer that asks for encryption to be disabled. Ubuntu’s documented installation process can require BitLocker to be turned off before installing alongside Windows on the same disk. A separate, unencrypted target disk provides another possible route, covered in the Ubuntu Desktop installation instructions.
If decryption is required, complete it in Windows before resizing or installing. Keep the computer connected to power and wait until Windows confirms completion. Check beforehand that your Windows edition and device configuration let you restore the encryption arrangement you want afterwards.
If you cannot obtain the recovery key, cannot change encryption under organisational policy, or do not want to decrypt the drive, stop here. Those are reasons to choose another installation method, not warnings to click past.
Step 2: Check Boot Mode, Secure Boot and Windows Shutdown Settings
Match the boot mode Windows already uses
Open System Information from Windows Search and find BIOS Mode. For the setup covered here, it should show UEFI. Also note the Secure Boot State for reference.
In Disk Management, open the physical disk’s Properties and check its partition style under Volumes. A modern UEFI Windows installation normally uses GPT.
Boot the Linux USB in UEFI mode too. If the firmware menu offers both a plain USB entry and one prefixed with UEFI, choose the UEFI entry. Booting installation media in Legacy or CSM mode can produce a Linux installation that does not match Windows. The Fedora Project’s UEFI documentation covers how the installer’s boot mode affects the installed system.
If Windows reports Legacy mode, do not simply change the firmware to UEFI and continue. That can prevent the existing installation from starting. Use a separate migration procedure or instructions intended for your current configuration.
Leave Secure Boot enabled when supported
Secure Boot and UEFI are not interchangeable terms. Secure Boot checks trusted signatures during startup; UEFI is the firmware environment in which it operates.
Do not disable Secure Boot automatically. Fedora supplies signed boot components for supported installations, while untrusted kernel modules can require extra work. The Fedora Secure Boot documentation describes those protections and restrictions.
Check your chosen distribution’s instructions before changing this setting. Third party graphics or wireless drivers may involve a signing or key enrolment step. Follow the installer’s prompts carefully, and keep the BitLocker recovery key available if a firmware change is necessary.
Avoid clearing firmware keys or resetting the TPM as general troubleshooting steps. Neither belongs in a routine dual boot installation.
Disable Windows Fast Startup
Windows Fast Startup preserves part of the system state instead of performing a conventional full shutdown. That is a poor fit for switching between operating systems that can access shared storage. The Arch Linux dual boot documentation details the filesystem risks associated with Fast Startup and hibernation.
In Windows, open Control Panel, then Power Options. Select Choose what the power buttons do, followed by Change settings that are currently unavailable. Clear Turn on fast startup and save the change. The option may be absent if hibernation is already disabled or unavailable.
Then shut Windows down fully before starting the Linux USB. Do not hibernate Windows and switch into Linux, or hibernate Linux and switch into Windows. Ordinary suspend is not an operating system switch either: resume the current system, save your work and shut it down first.
Windows Fast Startup is separate from a firmware setting called Fast Boot. Disabling one does not necessarily change the other.
Do not change storage controller settings blindly
If the Linux installer cannot see the internal SSD, stop before partitioning. Intel RST, RAID or VMD settings may be involved, but changing them can affect Windows too.
A direct switch from RST to AHCI can leave Windows unable to boot, and breaking a RAID arrangement can make data inaccessible. The Ubuntu documentation on Intel RST installation conflicts includes those warnings and the relevant reconfiguration path.
Use instructions matched to your computer and storage setup. “Change it to AHCI” is not a complete procedure for a Windows installation already using another controller mode.
Step 3: Make Room for Linux
Choose one disk or two
You can install both systems on one physical drive, using separate partitions, or place Linux on a second drive. A second SSD avoids shrinking the Windows system partition, but it does not remove the need to check where the installer places Linux’s boot files.
For a first installation, keeping Windows where it is and using clearly identified free space is usually easier than moving existing partitions. Do not rearrange recovery partitions just to make the disk map look tidy.
As a planning allowance rather than an official minimum, consider roughly 100–150 GiB for a general Linux desktop if your disk has room. Games, virtual machines, containers and large development projects can justify much more. Leave Windows enough space for its own applications, updates and temporary files.
Shrink Windows from Windows
Use Windows Disk Management to shrink the Windows volume rather than asking the Linux installer to resize an unfamiliar Windows layout. First finish pending Windows updates, restart, and confirm that Windows works normally.
- Right click Start and open Disk Management.
- Identify the Windows volume, usually C:, on the correct physical disk.
- Right click that volume and select Shrink Volume.
- Enter the amount of space to release, not the final size you want Windows to have.
- Confirm the operation and check that the released space appears as Unallocated.
Leave that space unallocated. Do not create a Windows volume in it or format it as NTFS. The Linux installer will create the partitions and filesystems it needs.
The shrink limit can be smaller than the free space shown in File Explorer because certain files cannot be moved by this operation. Microsoft’s volume shrinking documentation covers that restriction. If the available reduction is too small, reassess storage use or use another drive rather than forcing a resize with unfamiliar tools.
Identify the partitions you must preserve
Take a photograph or screenshot of the disk layout before installation. Record each physical drive’s model, capacity and partitions. Linux drive names will differ from Windows drive letters, so capacity and model are useful cross checks.
| Disk area | Typical purpose | Action during installation |
|---|---|---|
| Windows NTFS partition | Windows, applications and personal files | Preserve; do not format |
| EFI System Partition | UEFI boot files | Preserve; do not format an existing shared partition |
| Microsoft Reserved partition | Windows disk management use | Leave unchanged |
| Windows recovery or manufacturer partitions | Recovery tools and factory resources | Leave unchanged |
| Unallocated space reserved for Linux | Space released for the new installation | Create Linux partitions here |
If the layout contains dynamic disks, Storage Spaces, unfamiliar encryption layers or RAID volumes, pause. A basic partitioning walkthrough is not enough to handle those arrangements safely.
Step 4: Create a Linux USB and Test the Computer
Download the installation image from your distribution’s official download service. Choose a supported release and the correct architecture. For a typical Intel or AMD Windows PC, the image is usually labelled x86_64 or amd64.
Verify the download using the distribution’s published checksums and signature instructions where provided. Write the image with a suitable USB imaging application. This erases the USB drive, so check its identity before confirming. The full process is covered in creating a bootable Linux USB drive.
Use the computer’s one time boot menu to start the USB in UEFI mode. The access key varies by manufacturer. Choosing a temporary boot device is preferable to making several permanent firmware changes at once.
Select the live or trial session when available. Before opening the installer, test Wi-Fi, audio, keyboard, touchpad, display brightness and any external monitor you rely on. Check that the installer can identify the internal storage.
A live session is a useful screening tool, not a promise that every driver and power feature is fully configured. Our Linux hardware compatibility checklist provides a more detailed testing sequence.
If networking fails, resolve whether you need another driver or a temporary wired connection before committing. The guide to troubleshooting Linux Wi-Fi problems can help separate a missing driver from a connection setting.
Step 5: Install Linux Without Overwriting Windows
Use a guided alongside option when it matches your plan
Start the installer and work through language, keyboard, network and account settings. At the storage screen, look for an option to install alongside Windows or another operating system.
Linux Mint provides a guided alongside option that makes room for Linux and sets up an operating system selection menu. Its official installation guide also distinguishes that option from manual partitioning.
Do not assume that an alongside label means the installer has selected the space you prepared. Inspect the proposed disk layout. Check whether it will use existing unallocated space or resize another partition, and confirm the target drive.
On a shared Windows disk, never select Erase disk. On a separate Linux disk, an erase option may be appropriate only after you have confirmed that every partition on the selected drive can be destroyed.
Understand the manual layout before using it
Manual partitioning gives you control, but also makes you responsible for each mount point and format checkbox. If the guided option does not fit your layout and you cannot confidently identify the required partitions, stop and consult the distribution’s installation instructions.
For a straightforward Ubuntu or Mint style installation, the new Linux space commonly contains a root filesystem mounted at /. Ext4 is a conventional choice for that layout. Other distributions may default to Btrfs, use subvolumes, or require a separate boot partition.
A separate home partition is optional, not a requirement for dual boot. Do not place Linux’s home directory on a shared Windows NTFS partition. Linux permissions and application settings belong on a filesystem appropriate for Linux; the Linux filesystem and directory guide explains those roles.
Follow your distribution’s swap defaults unless you have a reason to change them. Swap can use a file, a partition or compressed RAM, depending on the installation. A dedicated swap partition equal to your RAM is not a universal requirement, and Linux hibernation needs separate planning.
Preserve the EFI System Partition
On a shared UEFI disk, the installer may reuse the existing EFI System Partition for Linux boot files. Reusing it must not mean formatting it. Windows and Linux can have separate boot directories within that partition.
Some installers show this partition mounted at /boot/efi; other boot arrangements use different mount points. Do not change the path simply to match a screenshot from another distribution.
If the installer reports insufficient EFI space, stop and review its documented requirements. Bootloader designs store different amounts of data there, so there is no single existing Windows EFI partition size that suits every Linux setup. Do not delete Windows boot files to make room.
With two physical drives, verify which EFI partition the installer will use. If you want each drive to boot independently, Linux’s boot files must be on its own drive too. Merely placing Linux’s root filesystem on the second SSD does not guarantee that independence.
Treat encryption as a separate decision
Windows encryption does not automatically encrypt Linux. Decide whether you need Linux disk encryption before accepting the partition layout, and check which encryption modes your chosen installer supports for dual boot.
Do not select an erase based encryption option on the Windows disk just because encryption sounds preferable. The storage action still matters. Keep Linux passphrases and recovery material separate from the machine, just as you did for Windows.
Read the final change summary
Before writing changes, confirm four things: the correct physical disk is selected; the Windows and recovery partitions remain; only intended new Linux partitions will be formatted; and an existing shared EFI partition will not be erased.
If the summary proposes deleting Windows, replacing the entire partition table or formatting an unidentified partition, cancel. This is the point to be slow. A progress bar is not a substitute for a checked disk layout.
Complete the installation with the computer connected to power. Remove the installation USB when prompted and restart.
Step 6: Test Both Systems Before Calling the Job Finished
Boot Linux from the internal drive and confirm that you reach the installed desktop, not the USB session. Check networking, storage, audio and your normal peripherals, then install the distribution’s available updates.
Next, restart into Windows. Use the Linux boot menu if Windows appears there, or select Windows Boot Manager from the firmware’s one time menu. Confirm that Windows starts and that your files and applications remain accessible.
Test both directions more than once, including a full shutdown and cold start. A Linux installation that boots while Windows is inaccessible is not a finished dual boot setup.
Install any required graphics driver through the distribution’s supported process. Avoid downloading a standalone driver installer as your first response to a graphics issue; see installing and troubleshooting NVIDIA and AMD drivers.
If BitLocker was suspended, restore protection after the startup configuration is stable. If Windows was decrypted, restore your chosen encryption setup where supported. Confirm that recovery material remains accessible and test startup again afterwards.
You can then add software through the distribution’s normal channels. The guide to native packages, Flatpak and Snap covers those choices without changing the dual boot arrangement.
Fix Common Dual Boot Startup Problems
The computer starts Windows immediately
Check firmware boot order before reinstalling anything. The Linux entry may exist but sit below Windows Boot Manager. Use the one time boot menu to test it, then adjust the default entry if it works.
Linux Mint may appear under the name Ubuntu in the firmware menu. That naming and the boot order issue are covered in Linux Mint’s EFI troubleshooting instructions.
Windows is missing from the Linux menu
A missing menu entry does not by itself mean Windows has been deleted. Test Windows Boot Manager directly from the firmware menu.
If Windows starts there, the problem is operating system detection or menu configuration. Follow the installed distribution’s bootloader instructions rather than applying commands intended for another distribution or a Legacy BIOS system.
A Secure Boot error appears
Check that you used current installation media supported by your distribution. Record the exact error before changing settings. A rejected installer, a rejected bootloader and a blocked third party driver are different problems.
Do not clear Secure Boot databases or remove security protections wholesale to see what happens. Use the distribution and computer manufacturer’s recovery procedures.
Windows requests a BitLocker key
Match the recovery key ID on screen with your saved records and use the corresponding key. Do not format the drive or start a Windows reset because the recovery screen appeared.
If the prompt returns at every startup, review the recent firmware and boot changes rather than treating repeated recovery as normal.
Neither system starts
Avoid making more partition changes. Try the firmware’s individual boot entries, then use your prepared recovery media to inspect the situation. Boot repair depends on whether the problem involves firmware entries, boot files, filesystems or the partitions themselves.
Use recovering a Linux system that will not boot for the diagnosis process. Keep the original backup untouched while attempting repairs.
Share Files Without Sharing System State
Keep each operating system’s applications and settings within its own installation. For documents needed by both, use a deliberately chosen shared location, such as an NTFS data partition, external storage or network storage. Windows does not normally browse a Linux ext4 installation through File Explorer.
Always shut Windows down fully before writing to its filesystems from Linux. Some NTFS drivers refuse write access when Windows has left a hibernated state; the NTFS-3G manual’s hibernation guidance describes that protective behaviour.
If a Windows volume opens read only or reports an unsafe state, return to Windows and resolve the shutdown or filesystem issue there. Do not force a writable mount or delete hibernation data just to dismiss the warning.
A shared partition is also not a backup. Both systems, and any mistake made from either, can affect its contents.
Keep a Safe Route Back to Windows
Retain the Linux USB, Windows recovery media, recovery keys and backup after installation. Keep both operating systems updated, and check that both still boot after major firmware or bootloader changes.
If you later remove Linux, first confirm that Windows starts directly through Windows Boot Manager. If it depends on a boot path you are about to delete, repair that dependency before removing partitions.
Only then delete partitions you have positively identified as belonging to Linux. Preserve the shared EFI System Partition and all Windows recovery partitions. Reclaiming the released space depends on its position on the disk; Windows cannot necessarily extend C: into free space located elsewhere.
A sound dual boot setup leaves both systems usable, backed up and recoverable. The installation is complete when you can choose either one confidently, not just when Linux reaches its desktop.