Microsoft 365 licensing explained

The business plans

For organizations with up to 300 users, Microsoft offers a family of business plans. Business Basic provides web and mobile versions of the Office apps along with email, OneDrive, SharePoint and Teams. Business Standard adds the desktop versions of the Office apps. Business Premium includes everything in Business Standard plus a significant set of security and device management tools.

Larger organizations, or those with specific needs, may use enterprise plans such as E3 and E5, which have no 300 user limit and include additional compliance and security capabilities. Microsoft also sells frontline plans for staff who mainly use mobile devices or shared computers. Names, bundles and prices change periodically, so confirm current details with your provider before making decisions.

Why Business Premium matters for security

The difference between Business Standard and Business Premium is mostly about security. Business Premium includes tools that many cyber insurers and security frameworks now expect, and buying them separately for each user often costs more than the upgrade. For many small organizations it is the most cost-effective way to meet common security requirements.

Having the licence is only half of the job. These features must be configured properly to provide any protection, and that configuration should be reviewed regularly as Microsoft adds and changes features over time. Many organizations pay for Business Premium for years without ever turning on its most important protections. Ask your IT provider for a short report showing which security features are enabled, which are not and why.

• Conditional access policies that control how and where users sign in
• Intune for managing and securing laptops and phones
• Microsoft Defender for Business for endpoint protection
• Additional email protection against phishing and malicious links
• Information protection tools for labelling sensitive documents

Mixing plans

You do not need to give every user the same plan. A warehouse worker who only needs email and Teams on a phone may be well served by a lower-cost plan, while office staff who handle sensitive information benefit from Business Premium. Mixing plans is common and supported, but keep the security baseline consistent across the organization wherever possible.

Be careful when mixing plans that some users do not end up outside your security policies. If conditional access or device management only applies to users with certain licences, an account on a cheaper plan could become the weakest point in your environment and an attractive target for attackers. Check your policies after any change.

Add-ons and common surprises

Microsoft sells many add-ons, including Teams Phone, additional archiving, advanced audit and Copilot. Some are valuable for specific roles, while others duplicate features you already have. Before buying an add-on, ask your provider whether your current plan already covers the need, or whether a partial feature set would be enough.

Common surprises include paying for licences assigned to former employees, buying monthly commitments at a higher rate when an annual commitment would suit you better and assuming that Microsoft backs up your data in the way a dedicated backup service would. Microsoft keeps the service running, but recovering from accidental deletion or ransomware is still your responsibility.

Reviewing your licences

Review your licences at least twice a year. Export the list of licensed users from the Microsoft 365 admin centre and compare it against your staff list. Remove licences from accounts that no longer need them and check that shared mailboxes are not consuming paid licences unnecessarily. Also check for unused add-ons and trials.

Then look at whether your plans still match how people work. Growth, new compliance obligations or a cyber insurance renewal may justify moving some or all users to a higher plan, while other users may be able to move down. A brief review with your IT provider usually pays for itself through recovered licences alone.