How to Dual Boot Windows 10 and Linux

Dual booting Windows 10 and Linux gives you the best of both worlds—Windows for gaming and general-purpose applications, and Linux for development, system administration, or open-source tooling. However, managing two operating systems on a single machine is a delicate operation that requires precision and planning.

This advanced guide walks you through the steps of setting up a clean and efficient dual-boot system using UEFI, GPT, and modern Linux distributions such as Ubuntu, Fedora, or Arch Linux.

Step 1: Prepare the Disk for Dual Booting

Option A: Windows Already Installed

1. Shrink the Windows partition:

• Go to Disk Management → Right-click the main partition (usually C:) → Shrink Volume.
• Leave at least 50 GB of unallocated space for Linux.

1. Disable Fast Startup & BitLocker:

• Control Panel → Power Options → Choose what power buttons do → Turn off Fast Startup.
• Ensure BitLocker is turned off on system drives (Control Panel > BitLocker).

1. Check EFI Partition:

   • Ensure you have an EFI System Partition (~100–500 MB, FAT32).

   • You can verify this using:

     diskpart
list disk
select disk 0
list partition


 Step 2: Create Linux Installation Media

1. Download your preferred Linux distro (e.g., Ubuntu LTS, Fedora Workstation).

2. Use Rufus or dd (on Linux/macOS) to create a bootable USB.

   sudo dd if=linux.iso of=/dev/sdX bs=4M status=progress && sync


3. Boot from the USB:

• Enter UEFI/BIOS settings → Disable Secure Boot (optional for some distros).
• Set the USB drive as first boot device.

Step 3: Install Linux Alongside Windows

1. Boot into Live Linux environment and start the installer.

2. Manual partitioning:

   • Use Something Else (Ubuntu) or Custom Partitioning option.

   • Identify the unallocated space.

   • Create the following partitions:

     • / (root): ext4, 30–60 GB

     • [Optional] /home: ext4, separate user data

     • [Optional] swap: 2–4 GB or based on RAM if you want hibernation

3. Set EFI partition:

   • Do not format the EFI System Partition (ESP).

   • Mount it as /boot/efi.

4. GRUB Bootloader:

   • Choose to install GRUB on the EFI partition (not MBR).

   • Typically ESP is /dev/sda1 or /dev/nvme0n1p1.

5. Finish installation and reboot.

Step 4: Configure UEFI Boot Order

After installation, the system may still boot directly into Windows. Here’s how to ensure GRUB appears:

1. Access UEFI firmware:

   • Hit F2, DEL,  ESC, or another key (depends on manufacturer).

2. Change Boot Order:

   • Set “ubuntu” or “Linux Boot Manager” above “Windows Boot Manager.”

3. Using Windows Command Line:

   bcdedit /set {bootmgr} path \EFI\ubuntu\grubx64.efi


Or install and use efibootmgr on Linux to reorder boot entries:

Optional Post-Install Steps

1. GRUB Customization

• Use tools like grub-customizer or manually edit /etc/default/grub:

  GRUB_TIMEOUT=5


  GRUB_DEFAULT=0


  GRUB_DISTRIBUTOR=`lsb_release -i -s`


2. Update GRUB after any config changes:

3. Re-enable Secure Boot (Optional)

If your Linux distribution supports signed bootloaders (e.g., Ubuntu), you may re-enable Secure Boot after installation.

Conclusion

Dual-booting Windows 10 and Linux is an excellent choice for users who want the best of both worlds: the familiarity and software compatibility of Windows, and the flexibility, performance, and open-source tools of Linux. Setting up a dual-boot system may sound complex at first—especially when dealing with modern hardware, UEFI firmware, and GPT partitioning—but with a clear, step-by-step approach, it becomes not only manageable but also highly rewarding.

The most important preparation is backing up your data. A simple mistake in partition selection can lead to loss of important files. Equally essential is verifying which partitions will be resized or formatted, ensuring you don’t overwrite your Windows installation. Having a live Linux USB drive ready is another must—it can be used for testing hardware compatibility, troubleshooting boot issues, or repairing the GRUB bootloader if something goes wrong.

Once the setup is complete, the benefits are immediate. For example, imagine a software developer who spends weekdays coding in Linux—taking advantage of tools like Docker, native package managers, and a powerful terminal—while on weekends, they boot into Windows to enjoy the latest PC games, which often have better driver support and compatibility. Instead of maintaining two separate machines, dual-booting allows them to switch seamlessly between these two environments depending on their needs.

With proper installation and configuration, a dual-boot system becomes robust, flexible, and future-proof. You’ll be free to choose the best operating system for each task—whether it’s development, gaming, design, or daily productivity—without compromise.