Email security is a crucial consideration for any UK small business or SME, especially when deciding whether to rely on Microsoft 365's built-in protections or to add third-party security applications. Microsoft 365 includes a range of tools designed to block spam, phishing, malware, and other threats, but some businesses wonder if these are enough or if extra layers from specialised vendors are necessary.
Why email security matters for UK SMEs
Email remains the primary channel for business communication and a common entry point for cyberattacks. A successful phishing attack or malware infection can lead to data loss, operational downtime, damage to customer trust, and potential breaches of UK data protection laws such as the Data Protection Act 2018 and UK GDPR. For example, a ransomware attack triggered by a malicious email could lock your files and disrupt your entire operation, costing time and money.
A typical scenario: balancing built-in tools and third-party apps
Consider a UK SME with around 50 employees using Microsoft 365 for email and collaboration. Their IT partner has configured Microsoft Defender for Office 365, enabling anti-phishing, anti-spam, and malware scanning. However, the business still experiences occasional phishing emails reaching staff inboxes. To reduce risk, the IT provider recommends adding a third-party email security gateway that offers advanced threat intelligence, sandboxing of suspicious attachments, and more granular policy controls. This layered approach helps catch threats that built-in tools might miss, improving overall protection without disrupting user productivity.
What to consider when comparing Microsoft 365 built-in tools vs third-party apps
- Coverage and features: Check if Microsoft 365's native tools meet your specific needs for anti-phishing, anti-malware, spam filtering, and data loss prevention. Third-party apps may offer enhanced detection, custom policies, or integration with other security systems.
- Compliance and audit readiness: Ensure your email security supports UK GDPR and ICO guidance by providing logging, reporting, and controls like multi-factor authentication (MFA) and access restrictions.
- Management and complexity: Adding third-party solutions can increase administrative overhead. Confirm your IT provider can manage these tools effectively and provide clear reporting.
- Cost vs benefit: Evaluate the pricing of third-party apps against the potential reduction in risk and impact of security incidents.
Practical checklist for UK SMEs
- Ask your IT provider to explain what Microsoft 365 security features are currently enabled and how they are configured.
- Request examples of recent email threats caught and missed, and how response times are handled.
- Check whether multi-factor authentication (MFA) is enforced for email access to reduce account compromise risk.
- Review your email retention and backup policies to ensure data can be recovered after an incident.
- Consider running phishing simulation exercises to test staff awareness and the effectiveness of email filters.
- When evaluating third-party apps, ask for details on how they integrate with Microsoft 365, their reporting capabilities, and support for compliance audits.
- Ensure your IT provider performs regular security reviews and updates policies based on evolving threats and ICO recommendations.
Ultimately, deciding between Microsoft 365's built-in email security and third-party applications depends on your business's risk appetite, compliance needs, and resources for managing IT security. A trusted managed IT provider can assess your current setup, identify gaps, and recommend a balanced approach that fits your budget and operational requirements. Engaging with an experienced IT advisor helps ensure your email security supports business continuity, protects sensitive data, and maintains customer confidence.