Antivirus for Windows 11: Free and Paid Options

Windows 11 ships with more built-in security than any previous release: Microsoft Defender, SmartScreen, memory integrity and hardware-backed protections tied to the TPM requirement.

That changes the question from 'which antivirus do I need' to 'is anything missing for me'.

Best free antivirus for Windows 11

Microsoft Defender for zero-effort protection, or Bitdefender Antivirus Free Edition if you prefer a third-party engine with a quiet interface. Both are permanent free options, not trials.

Three Windows 11 settings to check now

Core isolation and memory integrity under Device security. Controlled folder access under Ransomware protection. Reputation-based protection with potentially unwanted app blocking under App & browser control. All free, all worth two minutes.

Frequently asked questions

Does Windows 11 need antivirus?
Windows 11 already includes antivirus. You only need a third-party product if you want features it does not provide.
What is the best free antivirus for Windows 11?
Microsoft Defender if you want nothing installed; Bitdefender Antivirus Free Edition if you want a third-party engine.