Licensing Exchange

Exchange Server licensing offers two types of server licenses and client access licenses (CALs) for user or device access.

Server Licenses:

1. Standard Edition: Designed for small to medium-sized organizations, it supports mailbox functionality and other roles in larger Exchange deployments. This edition allows for 1 to 5 mailbox databases.

2. Enterprise Edition: Geared towards larger organizations, it provides support for more mailbox databases, ranging from 1 to 100.

Client Access Licenses (CALs): CALs are required for each user or device accessing the Exchange Server. Two types of CALs are available, and they are compatible with both server editions:

1. Standard CAL: Enhances user productivity across platforms, browsers, and mobile devices. It includes features that facilitate efficient work regardless of the user's location, while ensuring data protection. Users must have a Standard CAL to access its features.

2. Enterprise CAL: Helps organizations reduce costs and complexity in meeting regulatory compliance requirements. It offers integrated archiving and information protection capabilities. The Enterprise CAL is an add-on to the Standard CAL, meaning users must have both types of CALs to access Enterprise CAL features.

Customers should review the official licensing documentation and consult with a Microsoft licensing specialist to ensure compliance and determine the most suitable licensing approach for their specific requirements. 

Additional materials from Microsft:

Licensing Exchange Server 2019 on-premises