Antivirus subscriptions are one of the easiest recurring costs to cut, because Windows already includes a genuinely capable, free antivirus tool: Microsoft Defender. It's built into Windows 10 and 11, updates automatically, and consistently scores well in independent lab tests from organisations like AV-Test and AV-Comparatives. That said, there are reasons some users still add a second free tool, and it's worth understanding what each option actually offers before you decide.
Key takeaway: Microsoft Defender, already built into Windows and free, is sufficient real-time protection for most home users; free third-party tools like Malwarebytes are best used as an occasional second-opinion scanner rather than a full-time replacement.
Why Microsoft Defender is the sensible default
Defender runs automatically in the background on every Windows 10 and 11 PC, requires no installation, no account sign-up, and no subscription, and its detection rates in independent testing are competitive with paid suites from Norton, McAfee and Bitdefender. It also integrates tightly with Windows itself, including a firewall, ransomware protection (Controlled Folder Access), and SmartScreen web protection in Edge.
Do you need anything extra?
For most home users doing normal browsing, email and streaming, Defender alone is enough — you do not need to pay for a third-party antivirus subscription. Where a free second opinion helps is in occasional deep scans for specific threats like adware, browser hijackers, and potentially unwanted programs (PUPs), which Defender catches less consistently than dedicated tools built specifically for that job. Malwarebytes Free is the standard recommendation here: it's an on-demand scanner (not real-time protection in the free tier) that you run occasionally to catch anything Defender might have missed.
Tip: Running two full-time real-time antivirus programs simultaneously can cause conflicts and slow your PC down. Keep Defender as your always-on protection, and use something like Malwarebytes Free only for occasional manual scans, not as a second real-time guard.
Getting set up properly
- Confirm Defender is active: open Windows Security (search the Start menu), and check "Virus & threat protection" shows a green tick.
- Turn on Controlled Folder Access under "Virus & threat protection settings" for extra ransomware protection on your important folders.
- Optionally download Malwarebytes Free from malwarebytes.com for occasional supplementary scans — during install, decline the free trial of the paid real-time protection if you only want the manual scanner.
- Run a full Malwarebytes scan every month or two, or whenever your PC starts behaving unusually (pop-ups, slowdowns, unfamiliar browser toolbars).
- Keep Windows itself updated via Settings > Windows Update — many security improvements arrive through general OS updates, not just antivirus definition updates.
| Tool | Type | Best use |
|---|---|---|
| Microsoft Defender | Real-time, built-in | Full-time everyday protection |
| Malwarebytes Free | On-demand scanner | Occasional deep scans, PUP/adware removal |
| Third-party free suites (e.g. Avast Free, AVG Free) | Real-time | Alternative to Defender, but often push upsells |
Before you start: if you choose a third-party free antivirus instead of Defender, download it only from the official vendor site, and be cautious during install — free versions of Avast, AVG and similar tools are notorious for bundling browser extensions, toolbars and frequent upgrade nag screens.
What about free third-party suites like Avast or AVG?
These remain popular and do offer real, functional free antivirus protection, but they've also faced legitimate criticism over the years for aggressive upselling, bundled browser add-ons, and (in Avast's case) a past data-collection controversy that was resolved but dented trust. If you'd rather avoid the upsell pressure entirely, Defender plus an occasional Malwarebytes scan is the cleaner, hassle-free combination for most people.
Frequently asked questions
- Is Microsoft Defender actually good enough on its own?
- Yes, for typical home use. Independent testing labs consistently rate it competitively against paid alternatives for malware detection and protection.
- Should I ever pay for antivirus?
- Most home users don't need to. Paid suites add extras like VPNs, password managers and identity monitoring, which can be worth it if you want those bundled features specifically, but they aren't necessary just for baseline virus protection.
- Can I run Malwarebytes and Defender at the same time?
- Yes — Malwarebytes Free's on-demand scanning is designed to work alongside Defender without conflict, since it isn't providing full-time real-time protection in the free tier.