What Is Hybrid Join in Active Directory and Entra ID

What Is Hybrid Join?

Hybrid Join is a device identity model where Windows computers are joined to an on-premises Active Directory domain and simultaneously registered in Microsoft Entra ID. This allows a single device identity to exist across both on-premises and cloud environments.

Hybrid Join enables organizations to continue using traditional domain-based management while integrating cloud-based identity, access control, and security services.

Why Hybrid Join Exists

Many organizations rely on Active Directory for authentication, Group Policy, and legacy application support. At the same time, cloud services such as Microsoft 365 and modern security controls depend on Entra ID.

Hybrid Join was introduced to bridge these two worlds. It allows organizations to adopt cloud identity features without immediately replacing existing on-premises infrastructure.

How Hybrid Join Works

Hybrid Join relies on synchronization and device registration processes.

Device Registration

When a Windows device is joined to an Active Directory domain, it can be automatically registered with Microsoft Entra ID. This registration creates a corresponding device object in the cloud directory.

Directory Synchronization

User identities are synchronized from Active Directory to Entra ID using directory synchronization services. This ensures that users and devices share a consistent identity across environments.

Trust Relationship

The device maintains trust with both Active Directory and Entra ID. Authentication for on-premises resources continues to rely on Active Directory, while access to cloud resources is evaluated using Entra ID policies.

Hybrid Join vs Azure AD Join

Hybrid Join and Entra ID Join serve different scenarios.

Hybrid Join is designed for environments that still depend on on-premises Active Directory and domain-based management. Entra ID Join is a cloud-only model where devices are joined directly to Entra ID without a traditional domain.

Hybrid Join is commonly used during transitional phases, while Entra ID Join is often preferred for fully cloud-native environments.

Hybrid Join and Device Management

Hybrid Join enables devices to be managed using both traditional and modern tools.

Group Policy Integration

Hybrid-joined devices continue to receive Group Policy settings from Active Directory. This ensures compatibility with existing configuration and security policies.

Microsoft Intune Integration

Hybrid-joined devices can also be enrolled in Microsoft Intune. This allows organizations to apply compliance policies, configuration profiles, and Conditional Access controls.

Hybrid Join and Conditional Access

Once registered in Entra ID, hybrid-joined devices can be evaluated by Conditional Access policies. Access to cloud resources can be restricted based on device compliance, join state, and user risk signals.

This integration enables identity-based access control without removing traditional domain authentication.

Common Use Cases for Hybrid Join

Hybrid Join is commonly used in scenarios such as:

• Organizations migrating gradually to cloud identity
• Environments with legacy applications requiring Active Directory
• Windows devices managed with Group Policy and Intune
• Hybrid Microsoft 365 deployments

These use cases make Hybrid Join a practical solution for phased cloud adoption.

Limitations and Considerations

Hybrid Join adds complexity by introducing dependencies on both on-premises and cloud components. Proper configuration is required to avoid authentication issues, duplicate device objects, or inconsistent policy enforcement.

It is not always the optimal long-term solution. Many organizations plan to transition fully to cloud-native device join models over time.

Why Hybrid Join Matters Today

Hybrid Join remains relevant because many enterprises operate mixed environments. It provides continuity, flexibility, and a controlled path toward modern identity and access management.

Understanding Hybrid Join is essential for administrators managing Windows devices across hybrid infrastructures.