For many UK SMEs, Microsoft 365 is now the centre of the business. It holds your email, files, Teams chats, customer information, finance documents and day-to-day collaboration. That makes it incredibly useful, but it also means the security settings behind it deserve regular attention.

In 2026, reviewing Microsoft 365 security should not be seen as an IT housekeeping task. It is a business risk review. The question for owners and senior managers is simple: if someone gained access to your Microsoft 365 account today, what could they see, send, delete or steal?

The good news is that many of the most important protections are already available within Microsoft 365. The challenge is making sure they are switched on, configured properly and reviewed regularly.

Why Microsoft 365 Security Settings Matter to SMEs

Cyber criminals do not only target large enterprises. SMEs are often attractive because they may have valuable data, regular payment activity and fewer dedicated security resources. A compromised mailbox can lead to invoice fraud, customer data exposure, reputational damage and operational disruption.

Microsoft 365 is secure when it is managed properly, but default settings are not always enough for today’s threat landscape. A yearly review helps confirm that your business has kept pace with staff changes, new devices, hybrid working, new applications and evolving cyber risks.

1. Multi-Factor Authentication: The First Line of Defence

Multi-factor authentication, often called MFA, adds an extra check when someone signs in. Instead of relying only on a password, the user also confirms the login through an app, security key or another approved method.

For senior managers, the business benefit is clear: a stolen password should not be enough to access company email, files or Teams. MFA is one of the simplest and most effective ways to reduce account takeover risk.

Management question: Is MFA enforced for every user, including directors, finance staff, administrators and remote workers?

2. Conditional Access: Sensible Rules for Safer Sign-ins

Conditional Access is a way of applying sensible rules to Microsoft 365 sign-ins. For example, your business may decide that staff can access email from approved countries, trusted devices or managed company laptops, while unusual sign-ins require extra checks.

This is useful because not every login attempt carries the same level of risk. A finance manager signing in from their usual laptop in the UK is very different from an unexpected sign-in from overseas at 2am.

Management question: Do your Microsoft 365 access rules reflect how your business actually works today?

3. Microsoft Defender: Built-in Protection That Needs Attention

Microsoft Defender helps protect Microsoft 365 users, devices and email from threats such as malware, phishing and suspicious activity. Depending on your licence, it can provide protection for email, endpoints and wider cloud activity.

The important point for business leaders is that having Defender available is not the same as having it properly configured. Policies, alerts and response processes need to be reviewed so that threats are blocked or acted on quickly.

Management question: Are alerts being monitored, and does someone know what to do when Defender flags a problem?

4. Secure Score: A Board-Friendly Security Health Check

Microsoft Secure Score gives your organisation a measurable view of its Microsoft 365 security posture. It highlights recommended actions and helps track improvement over time. For senior managers, it can turn a complex technical topic into a more manageable business dashboard.

A higher score does not guarantee total protection, but it can show whether important settings are being ignored. It also helps create a prioritised improvement plan rather than relying on guesswork.

Management question: Do you know your current Secure Score, and is it reviewed as part of regular business risk management?

5. Backup: Microsoft 365 Is Not a Complete Backup Strategy

Many businesses assume that because their data is in Microsoft 365, it is automatically backed up in the way they need. Microsoft provides strong platform resilience, but that is not the same as a full business backup and recovery plan.

Accidental deletion, malicious deletion, ransomware, departed staff and retention settings can all create recovery challenges. SMEs should be clear about what can be restored, how far back they can go and how quickly the business could recover.

Management question: If a mailbox, SharePoint folder or Teams file library was deleted today, how quickly could you recover it?

6. Email Protection: Still the Front Door for Many Attacks

Email remains one of the most common ways criminals target SMEs. Fake invoices, supplier impersonation, password reset scams and malicious attachments can all arrive in an inbox looking convincing.

Good email protection should include spam and phishing filtering, attachment scanning, link protection where available, and correct domain settings such as SPF, DKIM and DMARC. Just as importantly, staff need to know how to report suspicious messages.

Management question: Are you actively reducing the risk of phishing and invoice fraud, or simply hoping staff will spot every fake email?

A Simple 2026 Microsoft 365 Security Review Checklist

• Confirm MFA is enforced for all users and administrators.
• Review Conditional Access rules for location, device and admin access.
• Check Microsoft Defender policies, alerts and response responsibilities.
• Review Microsoft Secure Score and agree priority actions.
• Confirm Microsoft 365 backup coverage, retention and restore testing.
• Review email protection settings, phishing controls and user reporting.
• Document who owns Microsoft 365 security inside the business.
• Schedule the next review before settings become outdated again.

Final Thoughts

Microsoft 365 is central to the way most SMEs operate, which is why its security settings should be treated as a business priority. A review does not have to be overly technical, but it should be structured, documented and repeated regularly.

For UK SME owners and senior managers, the goal is not to become cyber security experts. The goal is to ask the right questions, make sure the right protections are in place and reduce the chances of a preventable incident disrupting the business.

Call to action: If you have not reviewed your Microsoft 365 security settings recently, 2026 is the right time to start. A short review could identify simple changes that significantly improve your protection. Fruition stand ready to assist – contact us at helpdesk@fruitionsystems.co.uk.

Security | Fruition Systems | Microsoft Cloud Services in Hampshire