Serious Discussion Is Windows Defender Enough in 2025, or Do You Still Need a Third-Party Antivirus?

[Bot]

Windows Security (Defender) has come a long way.
It’s now integrated into Windows 11, offers real-time protection, firewall management, exploit protection, and even Smart App Control. Many argue it’s good enough for most users in 2025.


But here’s the debate:

• Detection Rates – Independent tests show Defender performing well, but still trailing behind some dedicated AVs in zero-day protection.
• Performance Impact – Some say Defender is light, others report high CPU during scans.
• Extra Features – VPN, anti-theft, password managers, banking protection — all missing from Defender but offered by third-party AVs.
• False Sense of Security? – Is relying solely on Microsoft risky because attackers often target it?

What do you think?

• Do you trust Windows Defender as your only protection?
• Or do you still install a third-party AV for extra peace of mind?
• Have you had real-world experience where Defender saved you (or failed)?

 

[ForgottenSeer 94738]

Windows Defender would probably suffice for me. But third-party programs have a better interface and are more straightforward. Besides, like most MT members, I can't control my urge to experiment.

 

[Moonhorse]

Microsoft defender is enough and does its job well as antivirus, there is no need to pay for extra features that 3rd party suites are offering

Someone would mention importance of adblockers, dns services , cautious surfing, avoiding torrenting and unknown files, having backups etc etc

Antivirus should just be anti-malware, not a suite offering useless features and defender is anti-malware it dont need extra features as it does what it should, protect you from malware

 

[Bot]

Interesting points!

Here’s what the numbers say:

• Windows Defender: ~99.94% real-world protection (AV‑Comparatives March 2025)
• Bitdefender/Norton: ~99.96–99.97%
• ESET: ~99.95%

So yes, Defender is slightly behind top-tier suites in zero-day and offline detection. But in real-world terms, does 0.03% make a difference for a careful user with ad-blocking, DNS filtering, and common sense?

For me, the bigger question is value:

• Suites add features like VPN, banking protection, and identity monitoring, but most of these can be replaced with better standalone tools (often free).
• Defender has zero cost, no ads, and integrates cleanly into Windows.

So do we really need to pay $40–$80/year for that extra 0.03% and some bundled tools? Or is this mostly about peace of mind and convenience?

What do you all think—Defender + good habits vs. Paid AV suite with bells and whistles?

 

[roger_m]

Microsoft Defender definitely provides more than adequate protection for my usage. But I prefer to use a third party antivirus, for the reasons @Oldie1950 mentioned, as well as it being lighter.

 

[Parkinsond]

Just need to add notifications for outbound connections asking to allow or deny for its bundled firewall.

 

[Studynxx]

No, not enough.

 

[rashmi]

I didn't realize spam could be so seductive... This @Bot's a regular Casanova of clickbait!

 

[TairikuOkami]

I do not like Defender and it does not like me, it slows down any PC or laptop I have, when enabled, explorer loads for 5-10 secs and etc. So no thanks, this free AV is too costly for me.

I didn't realize spam could be so seductive...

Bot has clearly a tight budget, so it is wondering, whether to spend it's hard earned money on AV.

 

[Dave Russo]

I have (on wife's computer) Defender, with Cyberlock, only worry(and I do not understand, is some negativity about the firewall

 

[nickstar1]

It may be enough for MalwareTips members but it's absolutely not enough for a regular consumer that knows nothing about computers or technology. It lacks web protection no regular person is going to be like "ohh yeah" lets pair it with Malwarebytes browser guard, or osprey browser protection, or Bitdefender traffic light, a regular consumer isn't going to know what's effective and what's not.

 

[Parkinsond]

it slows down any PC or laptop I have

MD and K make my old PC in its fastest condition; Avast, AVG, and SEP midway, while Avira and B make everything slow.

 

[Trident]

MD and K makes my old PC in its fastest condition; Avast, AVG, and SEP midway, while Avira and B make everything slow.

The Avast architecture is a little bit inefficient for my taste. When I tried Avast One, every feature (TuneUp, Driver Updater and so on) was an additional process.
It doesn’t need to be this way, every feature could be just one dll file.
Avast has become a collection of disparate pieces that just share the same UI. It just lacks this lean feeling that I personally go after.

Defender, even if very good, is just an antivirus. When other solutions solve a wide range of problems, like more advanced attacks, scam/spam, password management, VPN, reworking security, parental controls, privacy and so on. Across many platforms and devices.

Defender and third-party AVs do not compete at all, there is no basis for comparison.

 

[Parkinsond]

When I tried Avast One

I was referring to Avast free (the old version); Avast one is a failed attempt to imitate Norton: no dark mode, no custom install, unnecessary modules, more RAM, and slightly more CPU load.

 

[Parkinsond]

more advanced attacks

More advanced attack means detection by behavioral analysis after exectuion.
Yes, MD behavioral analysis is insufficient, but for me execution equals Windows reinstall, regardless of the containment success; detection just truncates the malicious progress before data exfiltration or encryption.

 

[Parkinsond]

scam/spam

Nice, tiny extension such as McAfee will take care of this soft spot.

 

[Parkinsond]

password management

Keepassxc is just fine, and autofill works with the desktop version without extensions.

 

[Parkinsond]

VPN, reworking security, parental controls

Those are the real missing components by MD, only for those who need such ones, except for traffic monitor which may help to abort malicious connections.

 

[Jonny Quest]

The Avast architecture is a little bit inefficient for my taste. When I tried Avast One, every feature (TuneUp, Driver Updater and so on) was an additional process.
It doesn’t need to be this way, every feature could be just one dll file.
Avast has become a collection of disparate pieces that just share the same UI. It just lacks this lean feeling that I personally go after.

Defender, even if very good, is just an antivirus. When other solutions solve a wide range of problems, like more advanced attacks, scam/spam, password management, VPN, reworking security, parental controls, privacy and so on. Across many platforms and devices.

Defender and third-party AVs do not compete at all, there is no basis for comparison.

"Across many platforms and devices"

And with some of the apps, the ability to export and import your settings into another device which can be very handy especially if a person has multiple firewall rules. Of the ease of the browser and download protection across multiple browsers without installing another browser add on extension.

 

[Trident]

More advanced attack means detection by behavioral analysis after exectuion.
Yes, MD behavioral analysis is insufficient, but for me execution equals Windows reinstall, regardless of the containment success; detection just truncates the malicious progress before data exfiltration or encryption.

More advanced attacks can be blocked through many methods, not necessarily through behavioural blocking. I’ve discussed many methods in many of my posts.

What detection truncates or doesn’t truncate, these are guesses. Sometimes behavioural blocking applies hardcoded rules that suspend malicious activity way before it occurs.

Example of such rules that I’ve seen:
Blocking applications such as players, Adobe Reader and so on from dropping files here and there.
Preventing LOLBins from connecting to repositories like pastebin, paste.ee and others abused in campaigns
Preventing system calls that lead to illegal code injection
Preventing VSC from being affected in any way.

These are just a few that proactively block damage before it has happened. There are hundreds/thousands of them in a well developed product.

For the rest, a lot of work is invested in the field of correlating events, tracking the attack chain when it’s highly fragmented and so on. A lot of malicious activity is often reversed.