Microsoft 365 security isn’t just about tools like Defender or Secure Score.
At the heart of Microsoft’s Zero Trust model is Conditional Access — the engine that decides who can access what, from where, and under which conditions.
If you’re an admin and not using Conditional Access intentionally, you’re relying on static controls in a dynamic threat landscape.
This guide breaks down Conditional Access in practical, admin-friendly terms.
What Is Conditional Access?
Conditional Access (CA) is Microsoft Entra ID’s policy-based access control system.
Instead of a simple “allow or deny,” CA evaluates signals such as:
- User or group identity
- Device compliance
- Location
- Risk level
- Application being accessed
Based on these signals, access is allowed, blocked, or restricted.
Think of it as a smart gatekeeper for your Microsoft 365 tenant.
Why Conditional Access Matters
Passwords get compromised.
Devices get lost.
Users sign in from everywhere.
Conditional Access helps you answer critical questions:
- Should this user be required to use MFA right now?
- Should this device be allowed to access corporate data?
- Should access be blocked based on risk or location?
Static security controls can’t answer these questions — CA can.
Core Components of Conditional Access
Every CA policy has five key parts:
1. Assignments
- Users or groups
- Cloud apps (e.g., Exchange, Teams, SharePoint)
- Conditions (location, device platform, risk level)
2. Conditions
Examples include:
- Sign-in risk (low, medium, high)
- Device state (compliant or not)
- Location (trusted vs unknown)
- Client apps (browser, legacy protocols)
3. Access Controls
- Require MFA
- Require compliant device
- Require approved client app
- Block access
4. Session Controls
- Limit download access
- Enforce browser-only access
- Control session lifetime
5. Policy State
- Report-only (test mode)
- On
- Off
Common Conditional Access Use Cases (Admins Should Start Here)
1. Require MFA for All Users
Baseline policy:
- All users
- All cloud apps
- Require MFA
This single policy eliminates most identity-based attacks.
2. Protect Admin Accounts
Admins should always have stricter rules:
- Require MFA
- Block access from risky locations
- Require compliant devices
Use dedicated admin accounts — not daily user identities.
3. Block Legacy Authentication
Legacy protocols bypass MFA entirely.
Create a policy to:
- Target all users
- Block legacy authentication clients
This closes one of the most abused attack paths.
4. Restrict Access from Unmanaged Devices
Limit sensitive apps to:
- Browser-only access
- Or compliant devices only
Especially useful for contractors and BYOD scenarios.
5. Location-Based Controls
Examples:
- Allow access only from trusted countries
- Require MFA when signing in from unknown locations
This reduces exposure without blocking remote work.
Report-Only Mode: Your Best Friend
Never deploy CA policies blind.
Use Report-only mode to:
- See who would be blocked
- Validate impact before enforcement
- Avoid locking out users
Always test policies in report-only for at least 1–2 weeks.
Avoid These Common Mistakes
❌ Applying policies to All Users without exclusions
❌ Forgetting to exclude emergency break-glass accounts
❌ Stacking too many policies without documentation
❌ Enforcing MFA everywhere without user communication
Conditional Access is powerful — but unforgiving if misconfigured.
Best Practices for a Sustainable CA Strategy
- Create break-glass accounts with exclusions
- Document every policy’s purpose
- Use naming conventions for policies
- Start simple, then layer controls
- Review policies quarterly
Conditional Access should evolve with your organization.
How Conditional Access Fits with Defender & Secure Score
Conditional Access works best when combined with:
- Microsoft Defender risk signals
- Secure Score recommendations
- Identity Protection alerts
Together, they form a dynamic, risk-aware security posture.
Final Thoughts
Conditional Access is not optional in modern Microsoft 365 environments.
It’s the difference between:
- Hoping your security holds
- And actively enforcing it
If you already use Microsoft 365, you already have the foundation — now it’s about using it correctly.
Need Help Designing Conditional Access Policies?
Techatix™ helps organizations design, deploy, and optimize Conditional Access strategies that balance security and productivity.
Contact us to get started.