EDR vs. Antivirus vs. MDR: What Small Businesses Need

EDR vs antivirus comes down to what each one watches: antivirus blocks files it already recognizes as malicious, while EDR (endpoint detection and response) records what actually happens on a device, so an attack that uses a stolen password, your own admin tools or malware built that morning can be spotted while it is in progress. Antivirus still belongs on every machine, EDR adds the visibility it lacks, and MDR adds the round-the-clock team that investigates EDR alerts and shuts the attack down.

If your small business still leans on antivirus as its main line of defense, you have a gap that attackers count on. Most modern endpoint products bundle antivirus and EDR in one agent, so the real buying questions are which tier you have and who reads the alerts.

At a glance	Antivirus	EDR	MDR
What it catches	Known malware it recognizes	Suspicious behavior on a device, including brand-new malware and misused admin tools	Attacks in progress, confirmed and acted on by analysts
Who is watching	No one; the software runs on its own	Your staff, if they have time to read the alerts	A security team, around the clock
When it acts	When a known threat appears	When behavior crosses a rule you configured	While an intrusion is unfolding
The response	Quarantines a file	Flags and records; someone still has to decide	An analyst investigates and can cut the machine off the network
Where it fits	Still belongs on every machine	The visibility layer antivirus lacks	The human layer most small teams cannot staff

Here is what changed, and what a small business should actually do about it.

What is the difference between EDR and antivirus?

Antivirus compares files against a list of known threats and quarantines matches. EDR, or endpoint detection and response, watches behavior instead: what a program does, which processes it spawns, what it touches. That is how it catches an attacker using a valid login and built-in Windows tools, where there is no malicious file for antivirus to recognize.

The practical difference is what happens after something is found. Antivirus deletes a file and considers the job done. EDR records the whole chain of activity so someone can see how far the intruder got, and it gives you the ability to isolate that machine. The catch is in the phrase "so someone can see." EDR produces alerts, and alerts need a human.

What is EPP, and how is it different from EDR and antivirus?

EPP, an endpoint protection platform, is the prevention layer: antivirus plus the controls around it, such as behavior-based malware detection, device control and host firewall management. EDR is the detection and response layer that records activity and lets someone investigate and isolate a machine. Endpoint security is the umbrella term for both. Vendors sell them as tiers of one agent, and the entry tiers are often EPP only. As of October 2026, SentinelOne's package table lists its endpoint protection platform in every tier but detection and response only from Singularity Complete up, and CrowdStrike's pricing page includes EDR only in Falcon Enterprise among its online bundles. Microsoft Defender for Business, included in Microsoft 365 Business Premium, has both.

So when a vendor or provider says you have endpoint protection, ask whether that means EPP alone or EPP with EDR, and how many days of activity it keeps. Our comparison of Defender for Business, CrowdStrike and SentinelOne lays out which tier includes what.

Is antivirus still enough for a small business?

No, not on its own. Antivirus catches commodity malware it has seen before, and it still earns its place on every machine. What it misses is the attacker who signs in with a valid password, quietly switches off your protections, and works toward your backups. That hands-on-keyboard style is exactly what smaller companies run into, and it strolls right past a scanner that is only checking names against a list.

The pattern shows up in the data. Verizon's 2026 Data Breach Investigations Report executive summary found ransomware in 48% of all breaches, up from 44% the year before, and says small organizations are disproportionately hit by it. For small and medium-sized businesses, the most common way in was exploitation of software vulnerabilities (26%), ahead of credential abuse (13%) and phishing (9%), break-ins that often involve no known-bad file at all. Small firms take the harder hit because the defenses in the middle of an attack, the ones that catch a break-in already in progress, usually are not there.

What does MDR actually do?

MDR, short for managed detection and response, pairs EDR software on your laptops and servers with a security team that watches the alerts every hour of every day. When something looks wrong at 2 a.m., a real analyst looks into it and can cut the affected machine off the network before the trouble spreads. Think of the difference between a smoke alarm and a fire crew already parked at the curb.

A typical service bundles endpoint detection and response on each device, active threat hunting, and a written plan for containment. The goal is not to bury you in more alerts. It is fewer nasty surprises, because someone else is sorting the signal from the noise on your behalf.

Do I need EDR, MDR, or both?

Almost every small business ends up wanting both, because they solve different halves of the problem. EDR is the sensor. MDR is the response. Buying EDR alone works only if you have someone in-house who will genuinely watch the console at odd hours and knows what to do when it lights up. Most companies under a hundred people do not, and an unwatched EDR console is an expensive way to record your own breach in detail.

You will also see managed EDR sold as a middle option. The usual difference: with managed EDR, a provider deploys and tunes the software and reviews alerts during the hours the agreement sets, while MDR adds triage, investigation and containment every hour of the year. Our managed detection and response service page sets the three side by side.

Why does response speed matter so much?

Because attackers take their time, and most companies are slow to notice. IBM's 2025 Cost of a Data Breach report found that organizations needed an average of 241 days to spot and contain a breach, and that was a nine-year best. Eight months gives a criminal room to read your email, map your vendors, and line up a fake invoice. MDR pulls that window down from months to minutes, because the watching never clocks out.

How much does EDR or MDR cost for a small business?

Both are usually billed per device or per user each month, and together they cost a small fraction of a bad day. IBM's Cost of a Data Breach Report 2026 puts the global average breach at a record USD 4.99 million, up 12% in a year. Most small businesses would not survive a sliver of that.

On the software side, as of October 2026, Microsoft Defender for Business, which includes EDR, costs $3.00 per user per month on its own or comes with Microsoft 365 Business Premium. CrowdStrike lists Falcon Enterprise, its first online bundle with EDR, at $184.99 per device per year, and SentinelOne lists Singularity Complete at $179.99 per endpoint per year through partners. MDR is quoted on top of, or including, the EDR license.

For a 25-person office, layered detection and response tends to land as a modest line item per seat, built into a broader security plan rather than bought as a one-off product. Our managed IT and cybersecurity services fold it in alongside the other protections a small team needs.

What should a small business check before buying EDR or MDR?

• Which tier you are on, and whether it includes EDR or only EPP.
• Whether every laptop, server and Mac has the agent, and how you will know when one drops off.
• How many days of activity the tool keeps, since many incidents are found weeks later.
• Who reads alerts at night and on weekends, and what they may do without calling you, such as isolating a laptop or disabling an account.
• Whether the response covers Microsoft 365 accounts as well as devices.
• How the old antivirus will be removed, so two agents do not fight over the same machine.

Do I still need backups, MFA, and email filtering?

Yes. EDR and MDR are layers on top of the fundamentals, not a swap for them. You still want multifactor authentication on every login, backups you have actually tested restoring, and filtering on your inbox, since most attacks open with a stolen credential or a convincing email. Detection is what catches the intruder who slips past those first walls. If you are unsure where your weak spots are, our rundown of the controls that actually stop attacks is a practical starting point.

Frequently asked questions

What is the difference between EDR and MDR?

EDR is the software that spots and records suspicious activity on a device. MDR wraps a 24/7 human team around that software to investigate the alerts and act on them. EDR on its own still needs someone on your staff watching it closely, which most small teams cannot realistically do.

Is EDR better than antivirus?

It catches a different and more dangerous class of attack, so it is better in that sense, but it is not a replacement. Keep antivirus running to handle known malware cheaply and automatically, and add EDR for the behavior-based attacks antivirus was never designed to see. Most modern endpoint products now bundle both.

Can't Microsoft Defender handle this for free?

Partly. Microsoft Defender Antivirus is built into Windows 10 and 11, but it is antivirus, not EDR. EDR comes with Defender for Business, which Microsoft 365 Business Premium includes, and with Defender for Endpoint Plan 2; Plan 1, the version in Microsoft 365 E3, leaves it out. What none of them includes is a team monitoring and responding to those alerts for you at all hours. MDR adds that human layer, often right on top of the Defender tools you already own.

Is EPP the same as antivirus?

Not quite. Antivirus is one part of an endpoint protection platform; EPP adds controls such as device control and firewall management, and usually detection that looks at behavior as well as signatures. EPP is still prevention. EDR is the part that records what happened and lets someone respond.

Which option fits a small team?

For most teams of 10 to 100 people: EDR on every device, often the Defender for Business already included in Microsoft 365 Business Premium, with MDR on top so someone answers alerts around the clock. Antivirus alone fits only a business with no sensitive data, no remote access and nothing worth ransoming.

What affects the cost, rollout and support of EDR or MDR?

Device and user count, the product tier, how long data is kept, server coverage and how much the MDR provider may do without asking. Rollout means deploying the agent through your device management tool, removing the old antivirus and tuning alerts for the first few weeks. Support splits between the vendor, who fixes the product, and whoever watches the console.

Is MDR only worth it for regulated industries?

No. Attackers do not check your industry first. Law firms, medical practices, and financial advisors have compliance reasons to add MDR, but any business with email, a bank account, and customer records benefits from around-the-clock detection. If you carry cyber liability coverage, a cyber insurance readiness assessment is a practical way to see how your current detection lines up with what the policy asks for.

How quickly can MDR stop an attack in progress?

A strong MDR team can isolate a compromised device within minutes of confirming a real alert, at any hour. That speed is the entire point. It turns what might have been an eight-month breach into a contained incident that never reaches your backups or your bank.

By Joel Baum for The NetSys Group, which has delivered managed IT, cybersecurity, and cloud services since 1998. Our engineers hold degrees in electrical and computer engineering and are certified Microsoft and Cisco instructors, serving businesses across NY, NJ, CT, PA, and Southwest Florida.

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