Traditional antivirus and Endpoint Detection and Response (EDR) get discussed as if they’re the same category of tool at different price points. They’re actually answering different questions, and understanding that difference matters for deciding what a business actually needs.
What traditional antivirus does
Signature-based antivirus compares files against a database of known malware. It’s effective against threats that have been seen before and catalogued, and largely blind to anything novel — a newly modified piece of malware, or an attack that doesn’t rely on a malicious file at all (living-off-the-land techniques using legitimate system tools).
What EDR adds
EDR monitors behavior continuously — process activity, network connections, file changes — and flags patterns that look like an attack regardless of whether the specific file has ever been seen before. It also gives responders visibility into what happened during an incident: what a process did, what it touched, where it tried to connect, which is invaluable during the scoping phase of incident response and largely absent from traditional antivirus.
Is the upgrade worth it for a small business?
In most cases, yes — EDR pricing has come down enough that it’s reasonably accessible for small and mid-sized businesses, and the behavioral detection genuinely catches things signature-based tools miss. Where it earns its cost most clearly is in businesses handling sensitive data or with any regulatory exposure, where "we didn’t know what happened" during an incident is a much worse position than having the visibility EDR provides.