If you're worried that you might have malware or a virus on your Mac, or that you might get one in the future, you've come to the right place. Here we explain how to remove malware and viruses from your Mac for free or cheaply, and more importantly how to prevent it from happing again (or in the first place).

The first thing to note is that it's actually quite unlikely you have a virus or any form of malware on your Mac – or at least not anything that can infect your Mac. You might unwittingly pass a virus onto a PC using friend, though, and you may fall for a phishing attempt where an email arrives in your inbox asking for login details.

That isn't to say that Mac malware doesn't exist, though. Every so often a new piece of Mac malware hits the headlines and it can cause havoc. Historically, Macs haven't been targeted by malware authors, mainly because they were considered niche. More people own PCs, and therefore targeting a PC means targeting a larger audience.

However, the Mac has become more popular in recent years, and as a result people with malicious intent have started to target them more frequently. According to Malwarebytes, there's been a 230% increase in Mac malware since July 2016.

In this article, we're focusing on malware and viruses, but ransomware has been a big threat to Macs lately following WannaCry and Petya. Find out more about how to remove Mac ransomware here.

What is malware?

Malware is different from other forms of malicious software such as viruses. Malware doesn't attempt to get into your machine without your knowledge like a virus does – it is malicious software disguised as legitimate software.

Perhaps you see an advert on a website, or you receive an email, either of which can trick you into installing it as you would any other program. When it is installed, it starts to gather information about you such as your banking details, in order to pass them on to nefarious individuals.

Where things get tricky is that most Mac malware pretends to be the very thing you want to use to get rid of it. Lots of malware is disguised as antivirus or antimalware software.

The way this scam works is that a hacker takes over a legitimate website, and this directs you to a fake website that pretends to scan your Mac. In doing so, it 'finds' malicious software (it doesn't, it's lying).

It then convinces you to download the program to check for the malware and remove it: this program itself is the malware. It may then continue to pretend to scan your Mac, pretend to find problems, and convince you to enter your credit card details in order to fix them

How to remove Mac malware for free

This point is important. You shouldn't be paying to remove Mac software – ever. You shouldn't pay to remove malware. In fact, we'd go so far to suggest that you shouldn't put your credit card details into any program or website that claims to be able to fix your computer.

Also, while we're at it: if somebody rings you claiming they have spotted malicious software on your computer and tries to convince you to hand over your bank details, put the phone down. It's a variation on the theme.

 So what should you do if a website suggests you have malicious software on your Mac?

  1. Quit the web browser you're using by pressing Command and Q on your keyboard, or right clicking on the icon of the browser and choosing Quit.
  2. Go to your Downloads folder and drag any install files, or files that you don't recognise, into the Trash.
  3. Empty the Trash by right clicking and choosing 'Empty Trash'

If you suspect that you've already installed malware on your Mac, follow these steps to remove it:

  1. If the app is open, check the name of the app.
  2. Move or close the app window
  3. Open the Utilities folder (Command-Shift-U)
  4. Open Activity Monitor
  5. Choose All Processes
  6. Look for the name of the app from step one, or an app that you don't recognise, and click Quit Process.
  7. Open the Applications folder and locate the app you just Quit Process for.
  8. Drag the unwanted app to the Trash.
  9. Empty the Trash.

How to protect your Mac from malware

Now that you've checked and removed any malware from your Mac, you'll want to ensure that your Mac doesn't get any malicious software in the future. Use the tips below to keep your Mac safe from malware.

  • Ensure your Mac is up to date. Open the App Store app and click Update All.
  • Turn on automatic updates. Open System Preferences and click App Store. Now select the option Automatically Check for Updates. Make sure both Install macOS Updates and Install System Data Files and Security Updates are also both selected.
  • Make sure your Mac only allows apps from trusted developers. Click on System Preferences > Security and Privacy and General. Check that the option under Allow Apps Download From is set to either Mac App Store or Mac App Store and Identified Developers. If it is set to Anywhere, then click on the Lock icon, enter your password, and change it to either Mac App Store or Mac App Store and Identified Developers.
  • Get your software from the Mac App Store or from developers you know and trust.
  • Install Mac antivirus software. Our pick of the best is BitDefender.