Microsoft 365 Business Premium vs E3 vs E5: Which Licence Do You Need?

Microsoft licensing is confusing in a way that feels deliberate, and the cost of getting it wrong runs in both directions. Under-licence and you are missing security controls you assumed you had. Over-licence and you pay every month for capability nobody in the business will ever open.

The most common mistake we see is neither of those, though. It is the assumption that the enterprise plans are simply better versions of the business plans, and that moving up is a security upgrade. That assumption is wrong in a specific and expensive way, and it is worth understanding before your next renewal.

This guide covers what each plan actually includes, what the July 2026 changes did, and how to work out which one fits a business of fifteen to a hundred and fifty people.

The Short Answer

If your organisation has fewer than three hundred users, Microsoft 365 Business Premium is almost certainly the right plan.

It bundles the security and device management tooling most businesses genuinely need, at a materially lower price than E3 plus the equivalent add-ons. For the size of business we work with, we recommend it in the overwhelming majority of cases, and we say so knowing that recommending the cheaper licence is not the obvious commercial move for an IT provider.

E3 becomes the right answer when you cross three hundred seats, or when you need specific enterprise capabilities around compliance, governance or archiving. E5 makes sense for a subset of users in regulated environments rather than as a blanket upgrade.

The rest of this article explains why.

The One Hard Rule: Three Hundred Seats

The Business family — Basic, Standard and Premium — is capped at three hundred users per tenant. This is a hard limit, not a guideline. User three hundred and one needs an Enterprise or Frontline licence.

For most of our clients this is academic. A business running fifteen to a hundred and fifty computers has a great deal of headroom, and the seat cap is not what should be driving the decision.

It matters if you are growing through the two hundreds. The step up to enterprise licensing is a meaningful per-user increase, and it is far better modelled twelve months out so that it arrives in a budget rather than as a surprise in a renewal quote.

What Each Plan Actually Is

All figures below are indicative Australian list prices, per user per month, excluding GST, on an annual commitment. Monthly billing typically costs around twenty per cent more. Confirm your exact rate with your licensing provider, because Microsoft’s Australian pricing follows a regional model rather than a direct currency conversion, and it moves.

The gap that matters most on that table is between Business Standard and Business Premium. Standard gives you the applications. Premium gives you the applications plus an entire security and device management layer — conditional access, device management, endpoint protection and email threat protection — for roughly twelve dollars more per user per month.

For any business handling client information, that twelve dollars is not a close decision. Buying those capabilities separately would cost considerably more, and Business Standard leaves you with no device management and no endpoint detection at all.

Why E3 Is Not a Security Upgrade

Here is the detail that surprises people, and it is the single most useful thing in this article.

Microsoft 365 E3 does not include endpoint detection and response.

Business Premium includes Defender for Business, which covers next-generation antivirus, attack surface reduction, threat and vulnerability management, EDR and automated investigation — the capability that cyber insurers now treat as a baseline requirement and that the Essential Eight effectively assumes. E3 does not include it. On E3 you add Defender for Endpoint separately, or you move up to E5.

E3 is best understood as a desktop, identity and mailbox plan operating at enterprise scale, with Windows Enterprise licensing and deeper compliance tooling attached. It raises the ceiling on seat count and adds governance capability. It does not, on its own, give you a better security posture than Business Premium.

This matters commercially, because the like-for-like comparison people run is usually wrong. Comparing Business Premium at around $32.90 against E3 at around $48 is not comparing equivalent things. Add the endpoint protection E3 lacks and the gap widens further, which is what tends to erase E3’s apparent advantage for businesses at the upper end of the SMB range. If someone has quoted you an E3 upgrade on security grounds, it is worth asking exactly which security capability you are gaining.

What Changed on 1 July 2026

Microsoft’s commercial pricing rose on 1 July 2026, with increases ranging from roughly five to thirty-three per cent depending on the plan. The increases landed hardest on Business Basic, Business Standard and the frontline F-series, with more modest rises on E3 and E5.

Business Premium did not move. Microsoft held it flat at its existing rate while raising the plans either side of it, which narrowed the gap from Business Standard and widened it from E3. For a business handling any sensitive information, that repricing made Business Premium the obvious choice by a clearer margin than before.

Microsoft also changed what sits inside the plans, and this received far less attention than the price rise:

• Mailbox storage doubled from 50GB to 100GB
• Defender for Office 365 Plan 1 was added to E3 and Office 365 E3, bringing Safe Links, Safe Attachments and impersonation protection to plans that previously lacked them
• E3 picked up Intune Remote Help, Intune Advanced Analytics and Intune Plan 2
• E5 gained Security Copilot, Intune Endpoint Privilege Management and Microsoft Cloud PKI
• Business Premium received Copilot Chat enhancements at no additional cost

The practical consequence is worth acting on. If you were paying separately for something Microsoft has now bundled in — email threat protection is the common one — you may be able to remove that line item. We would suggest checking, because nobody sends a notification telling you that you are now paying twice for the same capability.

Existing customers move to the new rates at their first renewal after 1 July 2026 rather than immediately, so if you have not renewed yet, this is worth looking at before you do.

When E3 or E5 Genuinely Is the Answer

We are not arguing that nobody should buy enterprise licensing. There are clear cases.

E3 makes sense when you are over three hundred users or will be within the year; when you need advanced eDiscovery or retention for legal or regulatory reasons; when you need unlimited archive mailboxes, which is common in legal and financial services; or when Windows Enterprise licensing is genuinely required. Note that if you buy E3 for the compliance depth, you will usually be adding endpoint protection on top.

E5 makes sense for a subset of users rather than an entire organisation. If a deal team, a finance function or a clinical group genuinely needs advanced compliance, insider risk tooling or identity governance, licensing those specific people at E5 is far more sensible than blanket-upgrading everybody. E5 also bundles Power BI Pro and Teams Phone, so if you are buying either separately for a group of users, the arithmetic can shift.

The phrase worth holding onto is that you are buying capability for the people who will use it, not a tier for the organisation.

Mixing Licences

You can run different plans in the same tenant, and for many businesses this is the most economical approach. The Business family must stay at or below three hundred licences, but there is no requirement that everybody hold the same plan.

A common and sensible pattern for a business of this size: Business Premium for knowledge workers, Frontline F-series licences for shift or field staff who need email and Teams but not desktop Office, and E5 for the handful of people with genuine compliance requirements.

One caution. Some services carry licensing conditions that apply across everyone who benefits from them, and identity and access management is the usual trap. Before building a mixed estate, it is worth having someone confirm the arrangement is compliant rather than assuming it is.

The Essential Eight Connection

This is where licensing stops being an administrative question and starts being a security one.

Business Premium, configured properly, will get a business to Essential Eight Maturity Level 1 comfortably and a good distance into Level 2. Entra ID P1 gives you conditional access and MFA enforcement. Intune handles device management and application control. Defender for Business covers endpoint protection and patching visibility.

The important qualification is the phrase “configured properly.” Owning the licence is not the same as having the control. We regularly assess environments holding Business Premium where conditional access has never been configured, Intune is not enrolling devices, and Defender is installed but nobody is reviewing what it reports. The capability was purchased and never switched on, which is the most expensive way to own software.

That distinction matters more than it used to. As we covered in our piece on cyber insurance requirements, underwriters are increasingly verifying controls rather than accepting a declaration, and a licence entitlement is not evidence of a working control. The same logic applies to Essential Eight maturity assessments.

So if the question is whether you need to upgrade your licence to improve your security position, the answer for most businesses on Business Premium is no. You need to finish configuring the one you already own. That is project work rather than a purchase order, and it is considerably cheaper than the upgrade.

What We Would Suggest

Start by working out what you are actually paying for. Run a licence audit: who holds what, who has left, who is on a plan that does not match what they do. Unused and mismatched licences are the most common form of waste we find, and they are the easiest to fix.

Then check whether Microsoft’s July repackaging has made anything you buy separately redundant.

Then, rather than looking at the upgrade path, look at whether the plan you hold is fully deployed. For the great majority of businesses in our size range, the gap between current security posture and where it should be is a configuration gap, not a licensing gap.

And review annually rather than at renewal. A renewal quote is a poor moment to discover that a third of your licences are the wrong shape.

Frequently Asked Questions

What is the difference between Business Premium and E3? Business Premium includes Entra ID P1, Intune, Defender for Business and Defender for Office 365 Plan 1, and is capped at 300 users. E3 removes the seat cap, adds Windows Enterprise licensing and deeper compliance and archiving capability, but does not include endpoint detection and response, which must be purchased separately.

Is E3 more secure than Business Premium? Not out of the box. Business Premium carries a deeper default security stack because it includes Defender for Business. E3 is primarily a scale and compliance plan rather than a security upgrade.

How many users can Business Premium support? Three hundred per tenant. It is a hard limit, and user 301 requires an Enterprise or Frontline licence.

How much does Microsoft 365 cost in Australia? Indicatively, Business Basic sits around $10, Business Standard around $21 and Business Premium around $32.90 per user per month excluding GST on an annual commitment. E3 is roughly $48 and E5 roughly $90. Monthly billing costs around twenty per cent more. Confirm current rates with your licensing provider, as Australian pricing follows Microsoft’s regional model and changes.

Did Microsoft 365 prices go up in 2026? Yes. Commercial pricing rose on 1 July 2026 by roughly five to thirty-three per cent depending on the plan. Business Premium was held flat. Existing customers move to the new rates at their first renewal after that date.

Can we run different Microsoft 365 plans in the same organisation? Yes, and for many businesses it is the most economical approach. The Business family must remain at or below 300 licences in total. Some services carry conditions that apply across all users who benefit from them, so it is worth confirming a mixed arrangement is compliant.

Do we need E5 to meet the Essential Eight? No. Business Premium, properly configured, reaches Maturity Level 1 comfortably and much of Level 2. The usual gap is configuration rather than licensing.

Getting the Licensing Right

Most businesses we review are paying for something they do not use and missing something they assume they have. Neither is obvious from a monthly invoice.

We supply Microsoft licensing and, more usefully, we can tell you whether what you hold matches what you need and whether the capability you have already paid for is actually switched on. That second question is where most of the value sits.

Not sure your licensing matches your business? Contact our friendly Brisbane team for a chat today.

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