What is the difference between antivirus and edr?
Antivirus checks files against a list of known threats.
EDR watches what's actually happening on your devices in real time, and can catch, stop and prevent attacks antivirus was never built to see.
For most UK businesses in 2026, antivirus alone is no longer enough on its own. Here's why, and what the difference actually means for you.
What does antivirus actually do?
Traditional antivirus works by comparison. It holds a database of known malware "signatures" and scans files against it. If a file matches something already known to be malicious, it gets blocked or quarantined.
That makes it fast, lightweight, and genuinely effective, but only against threats that have already been identified elsewhere.
The problem is what it can't see - anything new, anything that doesn't match a known signature, and anything that doesn't behave like a traditional file-based virus at all.
What is EDR and how is it different?
EDR stands for Endpoint Detection and Response. Instead of checking files against a list, it continuously monitors what's actually happening on a device - which processes are running, what they're doing, how they're connecting to other systems and looks for behaviour that looks like an attack, even if nothing on the device matches a known threat.
If it spots something suspicious, it doesn't just flag it. It can isolate the affected device from the network automatically, stopping an attack from spreading while it's investigated.
Something traditional antivirus was never designed to do.
It also keeps a detailed record of device activity, which matters when something does go wrong. Instead of guessing what happened, you can see exactly what a piece of malware touched, when, and how far it got.
Why isn't antivirus enough on its own anymore?
Because the threats it was built for aren't the main threat anymore. A lot of modern attacks are designed specifically to avoid looking like traditional malware:
Fileless attacks run in memory and never write a file to disk for antivirus to scan.
"Living off the land" techniques abuse legitimate tools already on the device - Windows utilities, scripting tools - so nothing about the process looks malicious on paper.
Human-operated ransomware often starts with stolen credentials, not a virus at all, so there's no malicious file to catch in the first place.
Antivirus is still useful. It just isn't the whole picture anymore, and hasn't been for a while.
Do I actually need EDR, or is antivirus enough for my business?
If any of the following apply, EDR stops being optional:
You hold customer data, financial records, or anything you'd need to explain losing.
Staff work remotely or hybrid, connecting from outside a controlled office network.
You're working toward, or hold, Cyber Essentials certification. Robust malware protection is one of the five core controls it checks.
You've never actually tested what would happen if a device on your network was compromised.
If none of those apply and you're a genuinely low-risk, fully office-based, no-sensitive-data operation, antivirus might still cover you. In practice, very few SMEs fit that description anymore.
Isn't having EDR installed enough on its own?
Not quite. EDR generates alerts, it doesn't decide on its own what's a genuine threat and what's a false alarm, and it doesn't always take the right containment action unassisted. Something still has to watch those alerts and act on them.
That's the part most businesses miss. A tool that flags a threat at 2AM on a Saturday is only useful if someone's actually watching it at 2AM on a Saturday. Left unmonitored, EDR just becomes a more detailed log of an attack that already happened.
That's the job of a Security Operations Centre (SOC) — analysts actively watching for alerts around the clock, triaging what's real, and responding immediately rather than waiting for someone to check an inbox on Monday morning.
How RefynIT approaches this
EDR is standard everywhere at RefynIT — every device we manage gets the same detection technology, the same monitoring capability, the same security foundation. We don't put meaningful protection behind a paywall. That's the whole point of not doing tiered security.
What varies is who's watching it and how fast they act. With Refyn Complete, that's a live team - analysts actively watching for alerts around the clock and stepping in immediately when something real happens, day or night, weekday or weekend. With Refyn Lite, the same detection is running and doing its job; it's the always-on human response sitting behind it that changes.
Think of it less as "extra security" and more as the difference between a house with an alarm system, and a house with an alarm system that someone is actually monitoring and can respond to in real time. The alarm itself doesn't change.
If you're not sure which level of response fits your business, that's exactly the kind of question we'd rather answer honestly than upsell you on.
Get in touch and we'll explain exactly how it works for your business.
