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Security software is something you can’t do without. While Windows keeps getting more and more secure, so the criminals keep finding new ways to attack. Things move so quickly that simply checking for known malware is no longer good enough: your antivirus program needs to monitor and analyse everything that’s happening on your system, so that even brand new “zero-day” exploits can be blocked.
The question is, out of the dozens of security packages on the market, which one should you trust to safeguard your computer and your precious data? Scroll down and you'll find our guide to what you need to know before buying a package, followed by our pick of the best antivirus software out there – a shortlist to help you pick your perfect protection.
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Best antivirus software: Buyer’s guide
Is it worth paying for a premium suite?
A few companies offer free antivirus software, but most packages you’ll have to pay for. The headline price you see on the publisher’s website isn’t the whole story, though. Often you can save money by investing in a two-year licence, or by buying a subscription for multiple computers.
Before you sign up, be sure to check third-party retailers too – many suites are significantly cheaper on Amazon than on the publisher’s own website. The same applies when the time comes to renew your subscription: the program will present a friendly link to easily renew at full-price, but you’re normally better off ignoring this and buying a whole new copy online.
Which edition do I need?
Most security publishers offer a range of products at different prices. The basic antivirus program will do the all-important job of scanning for malware, but probably not much else. The “Internet Security” suite will add extra features, such as tools to protect your privacy online. In many cases there’s also a top tier that adds features such as online backup or companion apps.
It’s also worth noting that most publishers like to brand their products with a year, and they can be quite aggressive about the timing: in some cases the 2017 packages have been out for months. But this doesn’t normally affect your licence: a 2016 subscription will often entitle you to step up to the latest version of the software whenever it becomes available.
Do I need a standalone firewall?
It used to be the case that every security suite worth its salt would include a firewall, to keep out intruders, and to identify and block dodgy software that tries to “phone home”. Nowadays, Windows comes with a very capable firewall of its own, and it’s quite common for the developers of security suites to leave this in place, rather than providing their own.
Advanced users, who feel at home customising network rules, may prefer a bespoke firewall – but unless you fall into that category we’d suggest that the Windows firewall is likely to provide all the protection you need.
Do I need protection while I’m browsing the web?
One of the easiest ways to get infected by malware is to inadvertently visit a dodgy website. Some sites are deliberately designed to spread malware disguised as desirable downloads – so-called “Trojan horse” attacks. Your security suite might well include a browser plugin that automatically blacklists such sites, so you can’t end up downloading something nasty by accident.
What’s harder to defend against is when a legitimate site is hacked, and starts serving up “drive-by downloads” to visitors. A good security suite will actively scan every web page you visit and every file that comes down the line, to ensure that attacks are spotted and intercepted before they can do any harm – although this has an inevitable impact on performance.
Why do some suites come with a standalone “safe browser”?
Web security is especially important on banking and shopping sites: if someone managed to hijack your transactions here, they could steal your financial details and cause very serious trouble. Some suites include an entire separate browser for use on such sites, that’s specifically engineered to shut out potential hackers.
Normally, a safe browser won’t support extensions at all, and will insist on encrypted connections. It may run in a sandbox or elevated environment to prevent other running processes from spying on what it’s doing. You can normally configure your security software to automatically switch from your regular browser to the safe one when you visit specific sites, for an effortless security boost when it’s needed.
How does email protection work?
As well as monitoring web page content, most security suites will also inspect incoming and outgoing email messages for dodgy attachments, or “phishing” links.
However, your security software can only examine messages that are stored on your PC, through a client like Outlook or Windows Mail. If you use Gmail or Hotmail, your security software has no way of looking inside attachments to see that they’re safe. Don’t worry too much about this, though: the very fact that attachments are stored in the cloud, rather than on your PC, makes it hard for malware to spread this way. Just don’t click on any unfamiliar links.
And what about protection for my phone and tablet?
Security experts have been warning for years that smartphones and tablets are just as vulnerable to malware attacks as computers, and many security suites are partnered by apps for Android and iOS – both free and paid-for.
Android is by far the bigger market, as its much more open architecture makes it easier for malware to spread. Offerings for iOS tend to be more limited, because the much stricter security model makes it very hard for both malware and security software to operate. If you like the cross-platform approach, it’s worth considering a suite that comes with a suitable companion app.
Best antivirus software
1. Kaspersky Internet Security 2017: Perfect protection, and packed with features
Price when reviewed:£30 (three PCs, one year)
The first thing to know about Kaspersky Internet Security 2017 is that it gave a flawless performance in independent malware protection tests by AV-Test.org. It achieved a perfect 100% protection score, against both known malware and never-before-seen threats. It’s also quite light on your system: on Windows 7, KIS 2017 slowed web-page loading times by a modest 7%, and its impact on applications was a mere 5%.
In addition to regular malware-detecting duties, Kaspersky is packed with features, including a special secure browser for banking and shopping, and parental controls for restricting access to potentially dangerous or corrupting sites. There’s a VPN too, which helps protect your online privacy by encrypting all your internet traffic.
Kaspersky Internet Security 2017 is quite loaded with features, so it might not be the perfect choice if you’re looking for a simple “set and forget” protection: in that case we suggest you consider Bitdefender (see below) as an alternative. All the same, Kaspersky offers excellent protection and versatility, making it our favourite security package overall.
2. Bitdefender Internet Security 2017: Silent security for those who don’t want to be bothered
Price when reviewed:£25 (three PCs, one year)
Bitdefender Internet Security is notable for its Autopilot mode, which suppresses all popups and alerts in favour of silent protection. That means it’s not the perfect choice if you’re regularly tinkering with obscure downloads and tweaking your network settings, but if you’re less technically inclined, or simply don’t like being interrupted, it’s a big attraction.
That’s not to say the package lacks depth, however. Advanced features include Safepay – an isolated web browser that’s designed to let you access banking and shopping sites safely – and BitDefender Central, an online console where you can monitor and manage all the devices registered to your BitDefender account.
Another nice touch is a Ransomware Protection module which monitors specific folders for suspicious behaviour. By default, your Documents, OneDrive and Pictures folders are protected, and you can add others: if anything tries to meddle with these files, it’ll be intercepted, making it impossible for Ransomware to lock up your data.
Best of all, Bitdefender does an impeccable job of protecting you from cyber-attacks. It achieved a perfect 100% score in AV-Test’s extensive testing, against both zero-day threats and a huge library of established malware, making BitDefender Internet Security 2016 a persuasive security option.
Buy Bitdefender Internet Security 2017 now
3. Avast Free Antivirus: The best free option for lightweight protection
Price: Free
As the name suggest, Avast Free Antivirus won’t cost you a thing. Yet it provides strong protection against online threats: AV-Test found that it achieved an excellent 99.4% protection rate against zero-day threats, and an even more impressive 99.9% against established malware. That’s a long way ahead of the Windows Defender software that comes built into Windows 10, and even outpaces some paid-for packages.
Avast isn’t overloaded with features, but it includes SafeZone, Avast’s Chromium-based safe browser that’s designed to be hard to hijack. There’s also a password manager, which lets you synchronise credentials across multiple devices, as long as they’re all connected to your Avast account.
The catch is that – as usual with free antivirus software – Avast doesn’t always run quietly in the background. You’ll see sporadic pop-ups urging you to upgrade to a paid-for package, and requesters that steer you towards premium features such as the performance optimiser, sandbox and firewall.
Even so, Avast Free Antivirus remains the best option for those who don’t want to pay. The occasional pop-up is easy to live with in exchange for such excellent protection.
Download Avast Free Antivirus now
4. AVG Internet Security: An effective security suite with a decent set of features
Price when reviewed:£15 (one PC, one year)
AVG is best known for its free antivirus product, but its paid-for Internet Security suite has a lot going for it. As well as regular protection from viruses and other attacks, you get AVG’s Data Safe, which lets you encrypt sensitive files; Web Protection, for scanning links and downloads; and Email Protection which lets you set up local mail scanning and spam protection. There’s also a highly configurable firewall, which promises to automatically block malicious programs based on their signatures or behaviour.
All of this integrates with the AVG Zen dashboard, which lets you manage multiple subscriptions and installations. So, for example, you could install AVG’s free antivirus package on a family PC, and check from your own computer that it’s running and receiving updates.
When it comes to performance, AVG doesn’t quite make it to the top of the table: AV-Test found it protected against a creditable 99.9% of known malware threats, but only 97.6% of attempted zero-day exploits. It’s a good value option, though: the AVG Protection bundle – which covers unlimited PCs and smartphones – can currently be found online for £18 a year, the same price as a three-PC licence. If you have a large number of devices to protect, it’s a tempting deal.
5. Trend Micro Internet Security: A stylish and capable antivirus suite
Price when reviewed:£30 (one PC, one year)
Trend Micro Internet Security makes a great first impression, with a tasteful grey and white front-end that coordinates well with the Windows 10 visual style. And it’s well equipped with features. As well as picking up viruses, the software can identify system components and applications that are known to be vulnerable, as well as junk files that are simply wasting space – such as temporary Windows and application files.
For those who like to get hands-on, there’s a reasonable degree of configurability, including scan settings that let you choose what gets automatically scanned and when. You can also prevent scripts from running on suspicious websites, and receive warnings if shares a dodgy page on Facebook or other social networks. If performance isn’t an absolute priority, you can also switch into “Hypersensitive” mode, which aggressively seeks out and intercepts programs that may cause trouble.
On that note, it's worth mentioning that Trend Micro made applications launch 30% more slowly – quite a steep performance penalty if you don’t have a fast SSD. It’s not the cheapest option either, since the standard licence is only for a single PC. But we can’t fault Trend Micro’s protection credentials: it delivered a perfect 100% score in all of AV-Test’s malware tests.
Buy Trend Micro Internet Security now
6. Norton Security 2016: An easy-to-use antivirus suite with a light impact on performance
Price when reviewed:£18 (one PC, one year)
Norton Security is one of the nimblest security suites we’ve tested: AV-Test found that it caused applications to open just 6% more slowly. The interface is very clean too, divided into Security, Identity and Performance.
The first of those contains only basic controls for turning antivirus functions on and off – but if you’re looking for more fine-grained controls, fear not. You can configure all sorts of options, such as what gets scanned, and what happens when a suspicious item is found, in the separate Settings interface.
The Identity pane meanwhile reveals Norton’s privacy-protection features. Those include the free Identity Safe password manager, and Norton Safe Web, which blocks malicious web pages and adds trust rating icons to web search results. The Performance tools are less useful – there’s not much here that can’t be replicated with free tools, or utilities that are built into Windows.
But while the suite may be short on useful extras, it nails the fundamentals. AV-Test found that the package achieved a flawless 100% protection rate against both zero-day threats and established malware. If you want a highly configurable package to simply sit in the background and keep you safe, Norton Security is a strong contender indeed.
7. Bullguard Internet Security: Strong protection and a good spread of features at an excellent price
Price when reviewed:£11 (three PCs, one year)
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BullGuard Internet Security Latest Edition - 1 Year - 3 User Licence with 5GB of Online Storage (PC)
BullGuard Internet Security is a low-cost suite – but that doesn’t mean it’s a low-grade product. In AV-Test’s zero-day tests, BullGuard couldn’t quite match the 100% scores achieved by others, but with a 97.6% protection rate, it wasn’t a million miles behind. And in the general malware test it successfully blocked every single threat. In all, it’s a package we’d be happy to entrust with our safety.
The suite’s most distinctive feature is an integrated cloud backup service. This includes both a simple backup module and a 5GB “Cloud Drive” in Windows Explorer, which lets you access your files as if they were on a regular network drive. It’s a great idea, although the price ramps up quickly if you need more space.
You also get BullGuard’s own firewall, and a Vulnerabilities scanner that checks OS settings, drivers and so forth. Plus, BullGuard’s parental controls provide more finely grained control over website blocking than Windows’ own filters, and give you more flexibility over scheduling. Its impact on system performance is modest too; partner that with decent protection and a very reasonable price and it’s an option that’s well worth your consideration.