How to dual boot Ubuntu and Windows safely

Updated 26 October 2026

Ubuntu and Windows can share one computer. At start-up you pick which to use.

Prepare

• Full backup first.
• Turn off Windows Fast Startup.
• Suspend BitLocker and keep the recovery key.
• Shrink the Windows partition in Disk Management to free 40 GB or more.

Install

1. Boot from the Ubuntu USB.
2. Choose Install Ubuntu, then Install alongside Windows.
3. Set the size split and continue.

Afterwards

A GRUB menu appears at every start-up. See the general dual boot guide.

More guides

• Best Linux for students
• Linux for first-time computer users
• Linux for small business computers

Browse Linux USB drives See all products