Picking the best antivirus software means finding one that keeps your PC or mobile device safe, doesn't consume a lot of system resources, is easy to use and stays out of the way until you need it. Here's what to look for.

Effectiveness

Antivirus software runs scans for known malware and can offer real-time protection. It can also watch for shady websites and suspicious links to keep you out of trouble. It can also offer ransomware protection and monitor unexpected behavior that may be a sign of new and not-yet-identified viruses and malware. You want antivirus software that can successfully identify these unknown online threats without flagging too many false positives.

You can determine an antivirus software’s effectiveness by looking at its detection rate in tests performed by labs like the AV-Test lab. None of this software is perfect -- malware is evolving all the time -- but you should look for software with an 80 to 90% detection rate.

Light on system resources

You don't want antivirus software that taxes your PC's resources, like RAM and CPU power. If after you install the program, websites open slowly, apps download sluggishly, software opens leisurely or copying files takes longer than expected, you may want to try another service. The good news is that all of our picks offer a free trial or money-back guarantee to let you try out the antivirus program before you buy, so if your system feels bogged-down after installation, you may want to keep looking.

Cost and discounts

Don't just pay the sticker price for antivirus protection. Before you buy, check for discounts on a company's website. Another way to save: You can trim your cost with smaller antivirus packages if you need to cover three or five devices rather than, say, 10. You may also find discounts on an app's Amazon page or at outlets like Best Buy.

During the purchase process, pay close attention to renewal costs. Most antivirus tools charge annual fees and only offer discounts for the first year (though you may be able to get a discount by paying for two years up front). These promotional prices might lead to you paying more -- sometimes as much as double the original amount -- for following years.

Bundled services

Antivirus software may come bundled with other security tools like a password manager and a VPN. Buying a security suite with all of these tools lets you manage everything from one account, saving you the hassle of managing multiple accounts -- and it can save you money, too.

However, the VPNs in these security bundles aren’t always the best tools available. You may want to purchase separate subscriptions or choose a VPN with antivirus if privacy is a major concern.

Privacy

To be effective, antivirus software needs to monitor what's going on with your PC, check in with company servers about unusual behavior and provide sound banking protection. The companies say they anonymize this technical data as much as possible to protect your privacy. If you want to know more, the security companies on our list post privacy policies on their websites, so you can read their privacy statements to learn what the companies do with the information you share.

Protection for other platforms

Microsoft is by far the biggest target for viruses and malware. Android is second, with 0.15% of apps installed on Android devices (with Google Play Protect) in the potentially harmful app, or PHA, category as of January 2024.

The threat to MacOS and especially iOS is low, in part because of the tight control Apple has over its app stores. While Mac does come under attack via side-loaded apps, it's rare, and if you download apps only from the Mac and iOS app stores and keep your guard up when clicking links and downloading files, you should be OK without an antivirus app on Apple devices. Thankfully, you can stay safe when downloading apps by sticking with official app stores, reading reviews and consulting privacy policies.

Issues with Avast

In test after test, Avast Antivirus for Windows performed well for malware detection, with options ranging from Avast free antivirus software to Avast Premium Security. We've included its antivirus in our list of recommended security app options before.

However, early in 2024, the Federal Trade Commission fined Avast $16.5 million to settle charges that claimed the company had sold customer browsing information to more than 100 third parties from 2014 to 2020. Avast allegedly collected the data through browser extensions and antivirus software and sold the data through its Jumpshot subsidiary, the FTC claims. As part of the settlement, Avast is prohibited from selling or licensing any web browsing data for advertising purposes.

In response to the initial reports in 2020, then-Avast CEO Ondřej Vlček said in a statement that he understood that his company's actions raised questions of trust. To address that, Avast terminated Jumpshot data collection in January 2020 and closed its operations. 

We hope the FTC actions mean that there will be no further Jumpshot-style activities and that Avast returns to glory as one of the best antivirus software options. Until then, we recommend using one of the many other solid choices in this realm (listed above). 

Issues with Kaspersky

Let's talk about Kaspersky Lab, specifically about the 2024 federal ban, announced on June 20, prohibiting Kaspersky from directly or indirectly selling antivirus or cybersecurity software or services in the US or to US citizens. This sweeping ban follows a more limited one in 2017 that prohibited Kaspersky software and services on federal government computers because of alleged ties between Kaspersky and the Russian government.

Based in Moscow, Kaspersky Lab has for years produced some of the highest-rated antivirus software for business antivirus needs and home customers. Its software consistently earned top scores and awards for virus and malware detection and endpoint protection from independent testing labs.

“Russia has shown time and again they have the capability and intent to exploit Russian companies, like Kaspersky Lab, to collect and weaponize sensitive US information, and we will continue to use every tool at our disposal to safeguard US national security and the American people," Secretary of Commerce Gina Raimondo said in the official announcement of the ban.

In a statement, Kaspersky said it "does not engage in activities which threaten US national security and, in fact, has made significant contributions with its reporting and protection from a variety of threat actors that targeted US interests and allies."

The Commerce Department recommends those who use Kaspersky software switch to replacement software from other security companies as soon as possible. To aid Kaspersky customers with the transition, Kaspersky will be allowed to provide antivirus updates to its software until Sept. 29, 2024, the department said.