Should you get free antivirus?

Every day new malware attacks of various descriptions target Windows PCs, and 2017 saw two huge ransomware attacks hit organisations including the NHS, highlighting the importance of protecting your PC.

It costs nothing to ensure your software is patched and up to date, and installing a decent antivirus package needn't cost you a penny either.

The good thing about installing a free product from one of the leading security companies is that they use the same 'engine' as their paid-for products.

You do get more if you buy an internet security suite, but what you get in the free version is stripped down package with a smaller feature set. Don't expect to get extras such as spam filtering, improved firewalls, parental controls, password managers and support for mobile devices, although some of this can be had for free. 

The free offerings from Avast, AVG, Avira, Bitdefender and Kaspersky all offer basic antivirus and anti-malware protection, giving you a good chance to keep your PC free of threats which could lose you data and take a lot of time to put right.

If you think a paid-for antivirus might be better for your needs, find out more about what they can offer and see our pick of the best in our best antivirus 2018 feature.

Since testing antivirus software with real malware requires a lot of time and effort, not to mention extremely specialist knowledge, we don't do this ourselves. Instead, we use the latest results from several well-respected independent test houses, including SE Labs, AV-test.org and AV Comparatives

Is free antivirus really free?

Yes it is. But you may trade off some privacy. For example, AVG’s privacy policy, showing what rights it takes over your personal and non-personal information when you download and use its free product, caused quite a furore when it was published. You grant it the right to share some of your (non-personal) information to third parties, which may include advertisers.

Right now, however, AVG is not sharing any data with third parties. It merely reserves the right to do so.

Some have said ‘Well, this is just AVG being more upfront about its policy; they all do it’, so we checked at what each company says in its privacy policy. They’re not all the same: some require you to opt out to prevent sharing and some ask you to opt in, but will respect your decision if you don’t, and some don’t share your information at all with third parties.

Best is Bitdefender, which claims not to share information with anybody outside its own company or subsidiaries. We think this is as it should be with a security product, but second-best is the assumption not to share, with an opt-in, should you want to receive ‘relevant’ offers. This is what Avast and Avira do. Panda does the same as AVG, requiring you to specifically unsubscribe to avoid security-related emails.

Does free antivirus software work?

Antivirus software is designed to prevent damaging programs from infecting your PC and laptop. All the free products here do that, but not all are as effective as others. As a secondary task, though, the full paid-for products should reduce the amount of unwanted advertising and offers that get through to you, and they usually offer quite a few other features as we mentioned above.

But without further ado, here are reviews of the leading free AV programs – you really can get something for nothing.

Best free antivirus 2018 - Antivirus software reviews

Avast Free Antivirus

Avast Free Antivirus

Unlike some firms, Avast doesn’t hide its free antivirus offering so you can’t find it. A big orange button on its homepage makes this version more obvious than its paid offerings, so it’s a good start.

As well as basic antivirus protection, it offers protection from unknown threats and a handy password manager so you can log into sites in your browser by remembering just one password.

You don’t get the browser extension that warns of fake sites (such as banks), nor a privacy shield or spam filtering. Those come with Avast’s Internet Security package, while Premier adds automatic software updating and a file shredder.

The good news is that Avast’s antivirus protection is solid. In AV-Test's December 2017 report, it found that 100% of zero-day attacks were protected against by Avast, and 100% of malware was detected.

It also offers good performance and usability, according to AV-Test's most recent report.

Avast asks you to opt-in to receive relevant offers, which may persuade some over AVG's forced opt-in to sharing data. Overall, then Avast is one of the best free antivirus packages around.

AVG Free Antivirus 2017

AVG Free Antivirus 2017

We’ve already mentioned AVG’s controversial privacy policy above, but in terms of the protection this free antivirus package offers, it’s still decent, though not currently the best.

AV-Test found that it protected against and detected 100% of threats in its December report, and that performance and usablility was on par with Avast's good scores.

We agree that AVG runs transparently in the background, and that you won't really notice it. And that’s exactly what you want from your antivirus.

AVG has a simple-to-understand dashboard so, if you do ever venture to it, it’s very clear whether it’s up to date and protecting your PC.

In addition to an AV engine, it also warns you of unsafe web links and can block unsafe email attachments.

If the privacy policy worries you, then read through it. It's in plain English and, as we mentioned above, AVG doesn't currently share any data - even non-personal data - with outside companies.

Bitdefender Antivirus Free Edition

Bitdefender Antivirus Free Edition

Bitdefender rightfully has an excellent reputation in the antivirus world. Its products are simple, robust and reliable - what more could you need?

While its full product suites can get expensive, its free version is a very good basic package.

The paid-for version received a Top Product award from AV-Test in December, thanks to excellent detection, protection and performance.

Overall, Bitdefender is easy to use, is lightweight and – in general – offers good protection for your PCs. 

Kaspersky Antivirus Free

Kaspersky Antivirus Free

Kaspersky is another big name in antivirus, and it recently launched a free version for PC.

It's no surprise that the free version doesn't come fully-featured. You won't get parental control, online payment protection, or VPN functionality. But you will get all of the essentials, including file, email and web antivirus, automatic updates, self-defense, quarantine and more.

Kaspersky scores well in AV-Test's December report, with almost 100% detection and protection, and top scores in both performance and usability.

It's a solid choice of free antivirus for your PC.

Avira Free Antivirus

Avira Free Antivirus

Avira has previously topped our list of the best free antivirus programs, and it’s still a very strong contender.

The interface is well designed and easy to use, and you'll get a SearchFree Toolbar: a website safety advisor and the option to block advertising companies from tracking you online.

File scans can be scheduled and by default there’s a quick scan set to repeat every 168 hours or, as we techies call it, weekly. We reckon a quick scan could run more frequently than this, though.

AV-Test gives Avira great scores in its latest tests, and awards it a 'Top Product'. It scored 100% detection and protection in December, although slightly less in November which puts its overall protection score at 4.5 rather than the 5 scored by Avast and AVG.

Ultimately, Avira does a good job – even when compared to paid-for Internet Security programs.

Microsoft Windows Defender

Windows Defender is built into Windows 10 and Windows 8, so it’s arguably the easiest option for most people since it’s probably in operation already unless you’ve disabled it or installed another antivirus program.

With Windows 7, you'll get Defender's predecessor - Security Essentials, but with Windows 8 and 10 you get the newer version that offers better protection against rootkits and bootkits. Defender is a credible and reliable AV engine. OK, it’s not the very best out there, but it certainly does the job.

AV-Test found that Windows Defender detected and protected against almost all attacks, and it scored well for performance. Usability is what lets it down.

There are better paid-for choices, but if you’re running Windows 8 or 10 with Defender built in, all you need to do is check that it’s enabled.