Microsoft Defender for Business costs $3.00 per user per month paid yearly as a standalone subscription, and it is already included in Microsoft 365 Business Premium at $22.00 per user per month paid yearly (both figures from Microsoft's Defender for Business product page, as of September 2026). A 12-person business already on Business Premium is therefore paying for managed endpoint protection whether or not anyone has ever opened the Defender portal. Before pricing a third-party antivirus subscription, the first question is whether that entitlement is switched on.
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The Short Answer
If the business runs Microsoft 365 Business Premium, endpoint protection is already paid for and the correct next step is deployment, not procurement. If it runs Business Standard or Business Basic, the choice is between adding Defender for Business at $3.00 per user per month paid yearly and buying a third-party endpoint product. If nobody on staff will log into a management console monthly, neither option is finished, and the real requirement is a managed service rather than a license.
What "Business Antivirus" Has to Mean at This Price Point
The category name is misleading. Consumer antivirus and business endpoint protection are not the same product sold to different buyers; they differ in what an administrator can see and control across a fleet. The distinction matters most in the three situations where a small business actually needs it: an employee laptop is lost, a device shows signs of compromise, or a cyber-insurance application asks what endpoint controls are in place.
Three things separate business-grade endpoint protection from a consumer subscription installed on twelve machines:
- Central visibility. One console showing every device, its protection status, and whether it is actually reporting in. Consumer products protect a device and tell that device's user. They do not tell the owner which of twelve laptops has been offline for six weeks.
- Policy enforcement. The ability to set a configuration once and have it apply to every device, including ones bought next month, rather than trusting each user to keep settings correct.
- Response, not just detection. Isolating a device from the network, rolling back a change, and reviewing what happened afterward. Detection alone tells you something occurred; response is what limits it.
Defender for Business supports up to 300 users, with a maximum of five devices per user. That ceiling is the practical boundary of the product: past 300 users, Microsoft routes buyers to its enterprise tier, and the comparison changes entirely.
| Capability | Consumer antivirus | Defender for Business | Managed endpoint service |
|---|---|---|---|
| Fleet-wide device inventory and status | No | Yes | Yes |
| Centrally enforced policy | No | Yes | Yes |
| Device isolation and remediation | No | Yes | Yes |
| Someone reviews alerts for you | No | No | Yes |
| Who administers it | Each employee | Your IT admin or MSP | The provider |
The row that decides most purchases is the fourth one. Defender for Business and every comparable licensed product will generate alerts. Neither will read them. A business with no internal IT person is buying a console nobody opens, which is why the answer for a lot of ten-to-thirty-person companies is a managed service on top of a license rather than a different license.
What You Are Probably Already Paying For
The most common overspend in this category is duplication. Microsoft 365 Business Premium at $22.00 per user per month paid yearly bundles Defender for Business together with device management, identity protection, and the Office applications. A business on that plan that also holds a separate per-seat antivirus subscription is paying twice for the same control, and the second product frequently is not deployed to every device anyway.
Microsoft lists Defender for Business at $3.00 per user per month and Microsoft 365 Business Premium at $22.00 per user per month, both paid yearly, on its Defender for Business product page as of September 2026. Prices exclude tax, and a 30-day trial is offered on each. Third-party endpoint pricing is quoted per device per year rather than per user per month, so any comparison has to normalize the two before the numbers mean anything.
That last point causes more confusion than it should. Microsoft prices per user and permits five devices per user. Most third-party endpoint vendors price per device per year. A ten-person business where several people use both a laptop and a desktop is buying ten seats from Microsoft and could be buying fifteen or more devices from a per-device vendor. Convert both to annual cost for the actual device count before comparing anything.
Use-Case Fit
- Already on Microsoft 365 Business Premium: deploy what is included. There is no procurement decision to make until the business exceeds 300 users or has a specific requirement Defender does not meet. The work is onboarding devices and confirming they report in, not evaluating vendors.
- On Business Standard or Basic, with someone who administers IT: adding Defender for Business at $3.00 per user per month paid yearly is usually the shortest path, because the identity and device management are already in the same tenant. Compare against a per-device third-party quote normalized to annual cost.
- Ten to thirty employees with no internal IT: license cost is the smaller half of the decision. Budget for a managed provider to own the console, or accept that alerts will go unread. A cheaper license that nobody administers is not a cheaper outcome.
- Mac-heavy or mixed fleet: confirm platform coverage and management parity before committing, since capability is frequently not identical across Windows, macOS, and mobile. The Mac antivirus comparison covers where the differences land.
- Regulated, or filling out a cyber-insurance application: the questionnaire will ask about centrally managed endpoint detection and response, multi-factor authentication, and logging. Answer the questionnaire first and buy against its requirements, because that document is the actual specification.
The Hidden Costs
Four costs sit outside the per-seat line item, and they are usually larger than the license.
Deployment time. Onboarding devices, setting policy, and confirming every machine reports in is a real project, not a checkbox. For a fleet of twenty mixed devices, plan on days rather than hours, especially where personal devices are used for work.
Administration. Somebody has to review alerts, investigate the ambiguous ones, and keep policy current as devices change. Licensed products do not do this. This is the cost most often left out of a comparison and the one that most often decides whether the tool works.
Plan-level dependencies. Endpoint protection sits alongside identity and device management, and the value of each depends on the others being configured. Buying endpoint protection while identity is unmanaged addresses one control and leaves the more commonly exploited one open.
Renewal drift. Third-party endpoint products are frequently sold with a heavy first-year promotional discount and renew at list. Check the renewal rate, not the introductory rate, and model year two before signing, exactly as you would with any other per-seat business subscription.
Which Should You Choose?
Start by checking the Microsoft 365 plan the business already holds. If it is Business Premium at $22.00 per user per month paid yearly, endpoint protection is bought and the remaining work is deployment. If it is Business Standard or Basic, price Defender for Business at $3.00 per user per month paid yearly against a per-device third-party quote normalized to the same device count and the same year, including the renewal year. Then answer the administration question honestly: if no named person will open a console monthly, add a managed provider to whichever license you choose, because that is the line item that determines whether any of this works. The full capability split between business and consumer products is covered in the business antivirus versus consumer antivirus breakdown.
Read the full endpoint security coverage on SoftwareSift for current pricing tiers and use-case segmentation before committing to a per-seat contract.
Frequently Asked Questions
- How much does Microsoft Defender for Business cost?
- $3.00 per user per month, paid yearly, as a standalone subscription, per Microsoft's Defender for Business product page as of September 2026. It is also included in Microsoft 365 Business Premium at $22.00 per user per month paid yearly. Prices exclude tax and both plans offer a 30-day trial.
- Is Defender for Business included in Microsoft 365 Business Premium?
- Yes. Business Premium bundles Defender for Business with device management, identity protection, data protection, and the Microsoft 365 applications. A business on Business Premium that also holds a separate antivirus subscription is paying for the same control twice.
- How many users does Defender for Business support?
- Up to 300 users, with a maximum of five devices per user. Past that ceiling Microsoft routes buyers to its enterprise endpoint tier, which is a different product with different pricing.
- Is consumer antivirus enough for a small business?
- It protects individual devices but gives the business owner no fleet-wide view, no centrally enforced policy, and no ability to isolate a compromised machine. For a single-person business that gap may be acceptable. For anything with employees, the missing piece is not detection quality, it is administration, and cyber-insurance questionnaires increasingly ask about exactly that.
- Do I still need a managed provider if I buy Defender for Business?
- If no one on staff will log into the console and review alerts, yes. A license generates alerts; it does not read them. For businesses of roughly ten to thirty people with no internal IT, the managed service is usually the larger and more important half of the budget.