Two antivirus shields greeting each other with bats behind them

In short – no. Running multiple antivirus programs is like riding a bike and having to take your friend’s bike home at the same time. Although it’s possible, it’s difficult and can put you in a lot of trouble. What’s the reason, and when should you use multiple antiviruses? Let’s dive right in and find out!

What happens if you have more than one antivirus program on your computer?

Without going into details, what happens is that your computer might meet its maker. But, with the proverbial devil always hiding in those details, the issue is much more complex than it sounds. So, let’s break down a few reasons why you shouldn’t use multiple AVs simultaneously.

You invite power-hungry monsters

There’s a rapidly growing number of online threats appearing today, and it’s almost impossible to count all the different types of hacks. So, you need an antivirus with some serious horsepower to protect the system from them. But with great power comes great responsibility computer resources’ consumption, particularly its Random-Access Memory (RAM).

Of course, not all antivirus programs are power-hungry monsters. That said, when used collectively, they won’t just make your computer much slower but also likely lead to other problems, such as operating system crashes.

You want to bring your friend’s bike with you. But riding a single bike can already drain you physically, much less two.

Running an individual antivirus uses a fair amount of power and performance, so what about two or more?
Your generosity will get you tired. And what about all the effort to keep both bikes stable?

Using two or more antiviruses can slow down your computer or even make your computer freeze or crash.

You watch a slaughterous battle between them

Still, the most common risk of running two or more antivirus programs is not eliminating the threat at all. And that’s because multiple antiviruses often interfere with each other. So, being too focused on their battle, neither identifies the virus.

But that’s not the only risk you’re running by using multiple AV programs simultaneously. For example, you might enable real-time protection on both antiviruses. After downloading a suspicious file, both start real-time scans and detect a threat. From there, both AVs attempt to quarantine the threat at the same time. What’s the result? Battery draining, error messages, freezes, and your operating system crashing down.

Controlling your bike with one hand and trying to navigate your friend's bike with another - good luck trying to keep your balance!

Just like that, two antivirus programs often interfere once they detect the same malicious program.
What happens when you can't keep your balance and the bikes crash into each other? You end up rolling into a ditch.

When there's a conflict between two antivirus programs, your device might go haywire.

You put them in infinite scan loops

And here’s the thing – that scenario above is not some rare, isolated case.

Let’s put it this way: we have antivirus A and antivirus B. When you view a file in a browser, antivirus A will examine it and run a signature/matching pattern check. Then, the OS (Operating System) will instruct antivirus B to scan the file. A new signal will be generated during the second reading. This will force antivirus A to do another scan. Due to this, both antivirus A and B will repeatedly scan files until they’ve exhausted all system resources, rendering the computer unusable.

Infinite loop between the operating system and multiple antivirus programs
What about trying to turn while controlling your own bike and navigating your friend’s. Or, better yet, trying to turn around?

Precisely this way, two antivirus programs on your computer repeatedly scan the malicious file one after the other.
Try as you might, there’s virtually no chance you won’t end up tumbling down to the ground.

The file-scanning loop usually uses the whole device's memory or simply crashes it.

You waste too much time on them

Just one antivirus can already require much work to configure and operate. Because antivirus software today has features galore, and you have to choose the ones your system needs. You also have to set up how each antivirus responds to threats when they are discovered. Additionally, you need to configure each antivirus’ scan exceptions (if you have any).

In other words, setting up one antivirus can be a massive pain in the neck (unless you’re working with an easy-to-configure AV like Surfshark Antivirus, wink-wink) – forget two. Having said that, sometimes, you can benefit from multiple antivirus programs.

When should you run multiple antivirus programs?

In one or two rare cases that you’ll find right down below. And, yeah, I know that all I’ve been talking about is why you don’t need multiple antivirus programs. But, hey, there are exceptions to every rule, and here they are. 

Another point of view

Be it the darkest times or not, you can’t deny that we live in one scary world with countless new daily threats. So, try as they might, even the best antivirus programs can’t always keep up.

With that in mind, I’d recommend running a second-opinion scanner on your device from time to time. In this regard, you have two main options:

Scanner-only products that don’t interfere with other AV programs and, therefore, work well with the existing security software. 

Cloud-based AV software that transfers some of your primary antivirus’ responsibilities to a cloud-based server, thus decreasing the load on your computer.

Some antiviruses have features that others do not

You might find yourself in a situation where your antivirus software can offer you only a quarantine vault and a firewall. But what happens when you decide that you need a real-time scanner as well? Or, what happens when it does have a real-time scanner, but its functionality isn’t enough?

It’s these very scenarios where a second antivirus program with extra functionality might come in handy. Of course, you still have to ensure that both antivirus programs cooperate while setting it up.

In conclusion: the less, the better

A person and antivirus shield hugging each other

The point I’ve been trying to drive home here is that you’re allowed to run multiple antivirus programs, but it’s seldom a good idea. Unless you like dealing with performance issues or wondering whether the threat has been eliminated, stick to one AV. Of course, ideally, you want an all-in-one security solution (like Surfshark One) that combines a powerful antivirus with an equally robust VPN and more. But a good standalone antivirus would be a good place to start too.

Choose one antivirus but make it count

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Is it OK to install two antivirus programs?

No, having multiple antivirus programs can slow down, freeze, or even crash your computer. If you decide you’re not satisfied with your current antivirus, we suggest uninstalling it first before installing a new one.

What happens if you have more than one antivirus program on your computer?

Running multiple antivirus programs simultaneously can cause battery draining, error messages, freezes, and operating system crashes.

Do Apple devices need a separate antivirus?

iOS devices are pretty secure and can get by without a third-party AV, but the same can’t be said about macOS devices. Though the macOS defense system is more secure than its counterparts, it still has security flaws. And that’s why malware like Silver Sparrow has been able to breach 30,000 Mac computers in the past.