Access Control Security Best Practices for 2025

Physical security is the foundation of your organization's overall security posture. An access control system is only as secure as its configuration and the practices around it. Here's our comprehensive guide to access control security best practices.

1. Implement Multi-Factor Authentication

A badge or card alone is no longer sufficient for high-security areas. Modern access control systems support multiple authentication factors:

• Something you have: Access card, key fob, or mobile credential
• Something you know: PIN code
• Something you are: Biometric (fingerprint, facial recognition)

For sensitive areas like server rooms, executive offices, or R&D labs, require at least two factors for entry.

2. Follow the Principle of Least Privilege

Users should have access only to the doors they need for their job function - nothing more. This sounds obvious, but it's commonly violated:

• Audit access rights quarterly
• Remove access immediately when employees change roles or leave
• Use access groups to manage permissions at scale
• Avoid giving "all doors" access except to essential personnel

3. Monitor and Review Access Logs

Your access control system generates valuable security intelligence. Use it:

• Set up alerts for after-hours access to sensitive areas
• Look for unusual patterns: repeated denied access, tailgating indicators
• Review logs when investigating security incidents
• Retain logs for compliance (many regulations require 1+ years)

4. Secure Your Credentials

The access cards and credentials themselves need protection:

• Use encrypted credential formats (avoid legacy 26-bit Wiegand where possible)
• Implement anti-passback to prevent card sharing
• Report and deactivate lost cards immediately
• Consider mobile credentials, which are harder to share and can't be cloned

5. Protect the Physical Infrastructure

Access control hardware needs physical protection too:

• Install controllers in secured locations (not publicly accessible areas)
• Use tamper-resistant enclosures and tamper alarms
• Secure network cabling in conduit
• Consider PoE with UPS backup for power resilience

6. Network Security

Modern access control systems are networked, which means standard IT security practices apply:

• Place access control devices on a dedicated VLAN
• Use encrypted connections (TLS) for all cloud communication
• Keep firmware and software updated
• Implement network monitoring for unusual traffic

7. Plan for Emergencies

Your access control system needs to support emergency scenarios:

• Configure emergency unlock ("fire alarm") integration
• Test lockdown procedures regularly
• Ensure offline operation works when network connectivity is lost
• Document manual override procedures for system failures

8. Regular Testing

Trust but verify. Regularly test your access control system:

• Attempt access with revoked credentials (they should fail)
• Verify door sensors are working (held-open and forced-open alarms)
• Test emergency procedures annually
• Consider penetration testing for high-security installations

Building a Security Culture

Technology alone isn't enough. Train your staff on security awareness:

• Never hold doors for unknown individuals (tailgating)
• Report suspicious behavior or unfamiliar faces
• Understand why access restrictions exist
• Know how to respond to security incidents

By combining robust technology with strong security practices and an aware workforce, you can significantly reduce the risk of unauthorized physical access to your facilities.