Is Switching to Passwordless Authentication Possible with Tools we Already Have?

We are all facing password fatigue, and many institutions we work with are asking for longer passwords and more of them to pair with authenticator apps and services, which cost extra on top of perhaps password managers for all those passwords.

Hear me out…what if we leapfrogged to the next step in strategy, passwordless authentication with an improved user experience and no extra cost? Admittedly, I have not spoken with examiners and auditors on this yet, and I’d highly recommend doing so if you plan to pursue this path.

The theory here is that using Windows 10 or 11 (specifically Windows Hello) and Microsoft 365 can set up a passwordless authentication requirement for personal computer login without requiring an external MFA solution.

1. Why Go Passwordless?

• • Stronger Security: Passwordless methods are far less susceptible to phishing, brute force attacks, and credential theft. In the 2025 Verizon Data Breach report, 30% of breaches in the financial industry were caused by compromised passwords.
  • Improved User Experience: Users can sign in faster and more conveniently—no need to remember or manage complex passwords.
  • Reduced IT Costs: Fewer password resets and less help desk support required.
    
    

2. What is Passwordless Authentication? 

Passwordless authentication replaces the traditional password with alternative, more secure methods such as biometrics, security keys, or one-time codes. The primary goal is to authenticate the user in a way that is resistant to most common attacks, while making the sign-in process faster and more intuitive. The authentication requirement can use a combination of any of the below methods.

• • Biometrics: Uses fingerprints, facial recognition, or iris scans.
  • PINs: Device-specific codes that are not transmitted over the network.
  • Security Keys: Hardware tokens based on FIDO2 or similar standards.
  • Certificate-based Authentication: Uses digital certificates stored on devices or smart cards.

3. How Windows Hello Works with Passwordless Authentication

Windows Hello leverages a combination of biometrics or PINs, device hardware (TPM chip), and cryptography. When a user sets up Windows Hello for Business:

• • The device generates a unique key pair (private and public keys) tied to the user and device.
  • The private key is stored securely and never leaves the user’s device.
  • When logging in, the user provides a biometric or PIN, which unlocks the private key and completes the authentication challenge with Azure AD or Active Directory.
  • No password is ever transmitted or stored centrally, making phishing and credential theft far less likely.
    
    

4. Microsoft 365 (M365) and Passwordless Authentication

With an M365 license—whether Business, E3, E5, or a similar enterprise plan—you may have access to Azure Active Directory (Azure AD). Azure AD supports multiple passwordless authentication options, including Windows Hello, Microsoft Authenticator, and FIDO2 security keys.

Prerequisites

1. 1. An active Microsoft 365 subscription (e.g., M365 Business Premium, E3, E5).
   2. Devices running supported versions of Windows 10 or Windows 11.
   3. Azure AD (included with M365).
   4. Administrative access to the Azure portal and Microsoft Endpoint Manager (Intune), if using device management.

Passwordless Methods in M365

1. 1. Windows Hello for Business: Enables biometric and PIN-based sign-in on Windows 11 devices.
   2. Microsoft Authenticator App: Push notifications or one-time codes for authentication.

User Experience Example

1. 1. User powers on their Windows 10/11 laptop.
   2. At the sign-in screen, they choose “Sign in with Windows Hello.”
   3. They can use facial recognition, fingerprint, or a PIN to authenticate.
   4. After successful authentication, they're logged in and can access M365 apps without entering a password.
      
      

5. Considerations and Best Practices

• • Device Compatibility: Ensure devices have the required hardware (biometric sensors, TPM chips, etc.).
  • Fallback Methods: Maintain emergency access (e.g., temporary password reset) for lost devices or hardware failures.
  • Phased Rollout: Start with pilot groups before full deployment.
  • Policy Enforcement: Use Conditional Access in Azure AD to require passwordless sign-in for sensitive applications.
  • Check with any third-party applications or integrations to be sure they work with Windows Hello as an identity provider. It does follow FIDO 2 and Web Authentication API, which should cover many integrations; however, better not to assume!

Switching to passwordless authentication with M365 and Windows Hello could be an affordable and simple solution to adding Multifactor Authentication for endpoint and other logins. With passwords being difficult to manage and a pain for most users, not to mention the security risk, perhaps we have the answer already in our technology stack?