CitadelSuite

CitadelLite Free Anti-VirusIn development · join the waiting list

Free anti-virus that keeps your laptop safe. Actually free.

CitadelLite is a 100% free anti-virus for everyday Windows laptops. No ads, no account, no trial that runs out. It makes sure the protection already inside Windows is switched on, up to date and scanning, and fixes the common gaps that leave laptops exposed.

Join the waiting listIs Windows Defender enough?
What CitadelLite checks

Everything that keeps a normal laptop safe, in one place

Green means protected. Amber means something needs attention. Red means you are exposed. Where Windows allows it, CitadelLite fixes the problem in one click.

Real-time protection

Makes sure Microsoft Defender's real-time and cloud-delivered protection are on, and tells you if tamper protection is off.

Up-to-date definitions

Checks how old the virus definitions are and updates them, so new threats are recognised.

Scans

Quick, full and custom scans, plus a weekly scheduled quick scan. Shows what was found and what was quarantined.

Firewall

Confirms Windows Firewall is on for home, work and public networks, and turns it back on if it isn't.

Windows Update

Spots failed or pending updates and restarts that are waiting, because most attacks use flaws that already have a fix.

Ransomware protection

Offers Windows' Controlled Folder Access to protect your documents and photos from ransomware. Your choice, never forced.

Unwanted apps

Turns on blocking of potentially unwanted apps: bundled toolbars, adware and fake "PC cleaners".

Safe browsing

Checks that SmartScreen is on, which warns you before you open known-dangerous downloads and websites.

Account safety

Flags risky set-ups such as everyday use of an administrator account, and checks whether device encryption is on.

Honest by design

What CitadelLite is, and what it isn't

We would rather be clear than oversell. CitadelLite does not invent its own virus-detection engine. It uses Microsoft Defender Antivirus, the engine already in Windows 10 and 11, and makes sure it, and the rest of Windows' security, is set up properly.

If you need more than the basics, CitadelFrame is our paid, AI-powered protection, and CitadelGate lets an IT provider look after your computers for you.

CitadelLite is

  • 100% free, with no ads and no account
  • For Windows 10 and Windows 11
  • Plain-language, with one-click fixes
  • Private: nothing leaves your laptop by default

CitadelLite is not

  • A trial that turns into a subscription
  • A replacement for backups
  • Business-grade managed protection (that's CitadelFrame and CitadelGate)
Waiting list

Be first to get CitadelLite

CitadelLite is in development. Leave your email and we will let you know the moment the signed Windows download is ready. We only use your email for that.

  • One email when it launches
  • No newsletter unless you ask for it
  • Unsubscribe or delete your details any time

Frequently asked questions

Is CitadelLite really free?

Yes. CitadelLite is 100% free for personal and small-business use, with no ads, no account and no time limit. It is how people get to know Citadel. Our paid products, CitadelFrame and CitadelGate, are separate.

Can I download it now?

Not yet. CitadelLite is in development and will be published once the Windows build is signed and tested. Join the waiting list and we will email you when it is ready.

Is it a full anti-virus?

CitadelLite uses Microsoft Defender Antivirus, the malware-detection engine built into Windows 10 and 11, as its engine. What CitadelLite adds is making sure Defender is actually protecting you, that the rest of Windows' security settings are right, and explaining problems in plain language with one-click fixes.

Why not just use Windows Defender on its own?

You can, and it is a solid engine. The trouble is that on many laptops protection is turned off, out of date, or undermined by a disabled firewall, missed updates or weak settings, and nobody notices. CitadelLite checks all of that for you and fixes it.

Will it slow my PC down?

CitadelLite itself does very little work: the scanning is done by Defender, which already runs on Windows. CitadelLite schedules a weekly quick scan at a quiet time, and you can change that.

What data does it collect?

None by default. CitadelLite works on your laptop and does not send scan results or files to us. There is an optional, off-by-default button to connect the laptop to an IT provider who uses CitadelGate.

I already have another anti-virus. Can I use CitadelLite?

Yes. If another anti-virus is the active protection on your laptop, CitadelLite detects it, reports its status and does not fight it. Only one real-time anti-virus should be active at a time.

Is it enough for my business?

For a sole trader or a very small office it covers the basics well. Businesses with several computers, client data or compliance obligations should look at CitadelFrame for AI-powered protection, or have an IT provider manage devices with CitadelGate.

Keep reading

Is Windows Defender enough? An honest answer9 signs your laptop has a virus, and what to doOur most advanced protection, powered by AIWindows patch management for small businesses