What happens if you never activate Windows 10 or 11?
Microsoft doesn't cripple systems anymore
If you are an avid Windows user, you might remember the old days of using Windows XP and Vista, when Microsoft used to give a 30-day grace period to get the feel of the OS without any activation. After the grace period, users weren't even allowed to access the OS and were forced to purchase the product key. However, starting with Windows 7, Microsoft stopped this and instead started forcing users to activate in other ways.
With Windows 10 and 11, Microsoft is even more lenient, especially regarding functionality. There's no concept of a grace or trial period. There are no restrictions to core features ever, and you can use it normally like you do on a licensed PC for work or leisure.
However, soon you'll realize some other limitations.
Lack of personalization
You have to face cosmetic limitations
While the core functionality remains intact, a non-activated Windows has visible cosmetic limitations. At first, you'll notice a watermark badge at the bottom right with the message "Activate Windows. Go to Settings to activate Windows." You'll see similar prompts every time you open Settings. Soon, Windows will start throwing pop-ups periodically to remind you of activation. Of course, these won't affect the PC's regular functionality, but the subtle reminders will be difficult to ignore over time.
Other than that, all Windows 11 personalization options will be disabled. That means you'll be stuck with the default wallpaper, unable to amend the system accent color or personalize the theme, and you can't personalize the lock screen. You won't have features like Windows Spotlight that automatically change the background of your OS, irrespective of whether you are using Windows Home or Pro edition.
These might seem minor inconveniences, but in the long term, you'll be itching to get your hands on these settings, especially if you are a regular user.
Lack of updates and security patches
You'll get updates, but not all
It's a common misconception that an unlicensed Windows 10 or 11 doesn't receive updates at all. However, that's not the case. This used to happen with Windows 7 and Vista SP2, but not anymore. But there's a catch.
While unlicensed Windows 10 and 11 do get updates, they are often delayed compared to the licensed version. Also, many security updates are not released for unlicensed users at all. Furthermore, if you are a licensed Windows user, you'll get frequent updates to patch up the glitches and bugs. These won't be frequently available for free users.
Obviously, there won't be free upgrades either. For example, Microsoft supports upgrading to Windows 11 from Windows 10 without any additional cost if your Windows 10 license is valid and transferable.
Is it legal to use Windows without activating it?
Technically, you are violating Microsoft's End User License Agreement (EULA) if you are using Windows 10 or 11 without activating it, so we do not recommend this practice. However, as of now, no free Windows OS personal users have received a legal warning from Microsoft. That might not be the case with commercial users, but it seems Microsoft is being lenient in this area.
When it comes to commercial use, you might get into trouble in other ways, too, when using an unlicensed Windows OS on your organizational PCs. If not you, your employees might try getting a Windows license in some dubious ways. So, it's best to invest in a commercial license and avoid any legal trouble.
And of course, at XDA we always recommend doing the right thing regardless, paying for authorized access to any software as relevant.
Should you activate Windows?
While it's completely safe to use Windows 10 or 11 without activating, I wouldn't suggest doing that because there are plenty of benefits to getting a licensed version. Also, you'll be free of tension (and guilt) when using a licensed version, because you'll get regular security updates and all the latest features.
However, not everyone may feel they need all features. For example, perhaps you have installed Windows on a virtual machine (VM) just for testing purposes or to run a particular Windows OS program. Or in a common use case, maybe you are switching from macOS to a Windows OS, and you may first just want to get a feel for it before actually purchasing it. Using it without a license is the best way to do that until you decide, since you'll get everything minus the personalization while you're making your assessment.
If you wish to activate your Windows OS, get a retail license (from an authorized vendor) instead of an OEM, if you have the option. This way, you can transfer the license to any other machines when upgrading, rather than having the license tied to your current hardware.