Do I need antivirus software for my Mac?

NO! To elaborate: there is no reason to ever install or run any 3rd party "cleaning", "optimizing", "speed-up", anti-virus, VPN or security apps on your Mac.  This documents describe what you need to know and do in order to protect your Mac: Effective defenses against malware and other threats - Apple Community and Recognize and avoid phishing messages, phony support calls, and other scams - Apple Support.  

There are no known viruses, i.e. self propagating, for Macs.  There are, however, adware and malware which require the user to install although unwittingly most of the time thru sneaky links, etc.   

Anti Virus developers try to group all types as viruses into their ad campaigns of fear.  They do a poor job of the detecting and isolating the adware and malware.  Since there are no viruses these apps use up a lot of system resources searching for what is non-existent and adversely affect system and app performance.

There is one app, Malwarebytes, which was developed by a long time contributor to these forums and a highly respected member of the computer security community, that is designed solely to seek out adware and known malware and remove it.  The free version is more than adequate for most users.  

Unless you're using a true VPN tunnel, such as between you and your employer's, school's or bank's servers, they provide false security from a privacy standpoint.  Read these two articles: Public VPN's are anything but private and Security Risks: The Dangers of Using Free VPNs (eccu.edu).  

Additionally, a new study ("Apple Offers Apps With Ties to Chinese Military”) is specifically about VPN apps in Apple’s App Store.

do I need anti virus software for my Mac?

Only if you want your Mac to run like it's 1995 all over again.

We see far too many people complaining here about poor performance and stability when the only cause turns out to be the presence of aftermarket "protection" like anti-virus software, so-called "cleaning" apps, and VPNs not issued by an employers.

Please do not fall for fear marketing.

Thank you for reaching out. 🤗

MacOS is the most secure operating system on the market. Privacy is at the very core of all Apple products and services.

Nothing can self-install, self-duplicate or self-sabotage your system.

I would advise against installing anything that interferes with that.

Don’t be fooled by clever marketing advertisement tactics that rely on fear to sell you a solution to a problem that doesn’t exist.

You don’t need Anti-Virus software.

All the best! 👋🏼😉

Smiliñ 😎 Brian

NO! you don't want or need antivirus software. the only thing those apps are good for is causing MAJOR issues within macOS while providing ZERO protection or benefit.

your best defence is safe computing habits. to implement that, please read Effective defenses against malware and other threats - Apple Community. it's a long article, but worth your time to read every word.

Nope! macOS has excellent built in protection against viruses and such. If You install third party anti virus; it only. Interferes with macOS’ses built in protection.

No!

It would just cause problems for your OS and interfere with Apple's own Gatekeeper/XProtect processes design to protect your Mac from malware.

Windows-like viruses that self-replicate and affect macOS don’t exist because of the underlying UNIX Foundation and permission limitations.

The macOS operating system resides in a sealed and read-only volume that can’t be opened by users or third-party applications.

Mac app security enhancements are sufficient to protect computers from malware.

Effective defenses against malware and other threats

Adware and Malware can affect computers and are often downloaded from “shady” websites or developers who inject them into downloads.

Source: User tip from @Kurt Lang

What is malware? - Apple Community

"Do I need antivirus software for my Mac"

No!