Exchange Online Service Description

Are you looking for a feature comparison of Office 365 subscriptions that include Exchange Online? If so, the Exchange Online service description article is what you need. You'll also learn about system requirements as well as storage and recipient requirements.

Note

If you need assistance with a task, or if you are troubleshooting a problem, you might find the following articles helpful: > Email for help creating and sending email. > Email in Office 365 for business - Admin Help> Fix Outlook and Office 365 problems with Microsoft Support and Recovery Assistant for Office 365> Email non-delivery reports in Office 365> Exchange Online Help

Microsoft Exchange Online is a hosted messaging solution that delivers the capabilities of Microsoft Exchange Server as a cloud-based service. It gives users access to email, calendar, contacts, and tasks from PCs, the web, and mobile devices. It integrates fully with Active Directory, enabling administrators to use group policies, as well as other administration tools, to manage Exchange Online features across their environment.

Organizations that subscribe to Exchange Online retain control over the messaging services they offer to users, but they do not have the operational burden of on-premises server software. With the Exchange Online hosted plans described in this document, email is hosted on servers that support multiple customers simultaneously. These servers are housed in Microsoft data centers and are accessible to users on a wide range of devices from inside a corporate network or over the Internet.

To compare features across plans, see Compare Office 365 for Business plans. To compare plans for Office 365 Germany, see Office 365 Germany subscription plans.

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What's new in Exchange Online

For information about new features in Exchange Online, see What's New in Exchange Online.

Office 365 plans for Exchange Online

Office 365 is available in a variety of plans to best meet the needs of your organization. For information about different plans, including standalone plan options and information on moving from one plan to another, see Office 365 Plan Options.

Each user who accesses the Exchange Online service must be assigned to a subscription plan, and each user subscription has its own mailbox. Folders and messages in these mailboxes reside on a computer running Exchange Server at a Microsoft data center.

User subscriptions are not required for conference rooms and shared mailboxes. These special mailbox types do not have login credentials. Instead, licensed users with the appropriate permissions manage and access them via delegation.

System requirements for Exchange Online

For system requirements for Office 365, the monthly subscription-based service available for business, education, and government organizations, please see Office 365 system requirements.

Storage and Recipient Limits for Exchange Online

For information about the storage and recipient limits available in the Exchange Online subscription plans, see Exchange Online Limits.

Feature availability across Office 365 plans

If your organization currently has subscriptions to Office 365 Small Business, Office 365 Small Business Premium, or Office 365 Midsize Business, visit your Message Center in the Microsoft 365 admin center or talk to your Office 365 provider for more details on how the new Office 365 Business plans impact you. To learn more about the new Office 365 Business plan family, see New Office 365 plans for small and mid-sized businesses.

Feature Exchange Server 2013 Exchange Server 2016 Office 365 Business Essentials Office 365 Business Premium Office 365 Enterprise E1 Office 365 Enterprise E3 Office 365 Enterprise E5 Office 365 Enterprise F1
Planning and Deployment
Hybrid deployment supported Yes Yes Yes16 Yes16 Yes Yes Yes Yes16
IMAP migration supported Yes Yes Yes Yes Yes Yes Yes Yes
Cutover migration supported Yes Yes Yes Yes Yes Yes Yes Yes
Staged migration supported No No Yes Yes Yes Yes Yes Yes
Permissions Exchange Server 2013 Exchange Server 2016 Office 365 Business Essentials Office 365 Business Premium Office 365 Enterprise E1 Office 365 Enterprise E3 Office 365 Enterprise E5 Office 365 Enterprise F1
Role-Based Permissions Yes Yes Yes Yes Yes Yes Yes No
Role Groups Yes Yes Yes Yes Yes Yes Yes No
Role Assignment Policies Yes Yes Yes Yes Yes Yes Yes No
Message Policy and Compliance Exchange Server 2013 Exchange Server 2016 Office 365 Business Essentials Office 365 Business Premium Office 365 Enterprise E1 Office 365 Enterprise E3 Office 365 Enterprise E5 Office 365 Enterprise F1
Archiving Exchange Online-based Mailboxes No No Yes Yes Yes Yes Yes No
Cloud-Based Archiving of On-Premises Mailboxes Yes 1 Yes1 No No Yes Yes Yes No
Messaging Records Management (MRM) Retention Tags and Retention Policies Yes Yes Yes Yes Yes Yes Yes Yes
Encryption of data at rest (BitLocker) Yes15 Yes15 Yes Yes Yes Yes Yes Yes
IRM using Azure Information Protection No Yes No2 No2 No2 Yes Yes No2
IRM using Windows Server AD RMS Yes3 Yes3 Yes3 Yes3 Yes3 Yes3 Yes3 Yes3
Office 365 Message Encryption Yes13 Yes13 No2 No2 No2 Yes Yes No2
Customer Key for Office 36522 No No No No No No Yes No
S/MIME Yes15 Yes15 Yes Yes Yes Yes Yes Yes
In-Place Hold and Litigation Hold Yes Yes No No No Yes Yes No
In-Place eDiscovery Yes20 Yes20 Yes20 Yes20 Yes20 Yes20 Yes20 Yes
Transport Rules Yes 4 Yes4 Yes4 Yes4 Yes4 Yes4 Yes4 Yes4
Data Loss Prevention Yes5, 14 Yes5, 14 No No No Yes Yes No
Journaling Yes Yes Yes Yes Yes Yes Yes Yes
Anti-Spam and Anti-Malware Protection Exchange Server 2013 Exchange Server 2016 Office 365 Business Essentials Office 365 Business Premium Office 365 Enterprise E1 Office 365 Enterprise E3 Office 365 Enterprise E5 Office 365 Enterprise F1
Built-In Anti-Spam Protection Yes 6 Yes 6 Yes Yes Yes Yes Yes Yes
Customize Anti-Spam Policies Yes, but only via PowerShell Yes, but only via PowerShell Yes Yes Yes Yes Yes Yes 7
Built-In Anti-Malware Protection Yes 8 Yes 8 Yes8 Yes8 Yes8 Yes8 Yes8 Yes8
Customize Anti-Malware Policies Yes Yes Yes Yes Yes Yes Yes Yes 7
Quarantine - administrator management Yes Yes Yes Yes Yes Yes Yes Yes 7
Quarantine - end-user self-management No No Yes Yes Yes Yes Yes Yes
Advanced Threat Protection No Yes No No No No Yes No
Mail Flow Exchange Server 2013 Exchange Server 2016 Office 365 Business Essentials Office 365 Business Premium Office 365 Enterprise E1 Office 365 Enterprise E3 Office 365 Enterprise E5 Office 365 Enterprise F1
Custom Routing of Outbound Mail Yes Yes Yes Yes Yes Yes Yes Yes
Secure Messaging with a Trusted Partner Yes Yes Yes Yes Yes Yes Yes Yes
Conditional Mail Routing No No Yes Yes Yes Yes Yes Yes
Adding a Partner to an Inbound Safe List No No Yes Yes Yes Yes Yes Yes
Hybrid Email Routing Yes Yes Yes16 Yes16 Yes Yes Yes Yes
Recipients Exchange Server 2013 Exchange Server 2016 Office 365 Business Essentials Office 365 Business Premium Office 365 Enterprise E1 Office 365 Enterprise E3 Office 365 Enterprise E5 Office 365 Enterprise F1
Capacity Alerts Yes Yes Yes Yes Yes Yes Yes Yes
Clutter Yes No Yes Yes Yes Yes Yes Yes
MailTips Yes Yes Yes Yes Yes Yes Yes Yes
Delegate Access Yes Yes Yes Yes Yes Yes Yes No24
Inbox Rules Yes Yes Yes Yes Yes Yes Yes No
Connected Accounts Yes Yes Yes Yes Yes17 Yes17 Yes17 Yes17
Inactive Mailboxes No No No9 No9 No9 Yes Yes No 9
Offline Address Book Yes Yes Yes Yes Yes Yes Yes Yes
Address Book Policies Yes Yes Yes Yes Yes Yes Yes Yes
Hierarchical Address Book Yes Yes Yes Yes Yes Yes Yes No
Address Lists and Global Address List Yes Yes Yes Yes Yes18 Yes18 Yes18 Yes18
Office 365 Groups No No Yes Yes Yes Yes Yes Yes
Distribution Groups Yes Yes Yes Yes Yes Yes Yes Yes
External Contacts (global) Yes Yes Yes Yes Yes Yes Yes Yes
Universal Contact Card Yes Yes Yes Yes Yes Yes Yes Yes
Contact Linking with Social Networks Yes Yes Yes Yes Yes Yes Yes Yes
Resource Mailboxes Yes Yes Yes Yes Yes Yes Yes Yes
Conference Room Management Yes Yes Yes Yes Yes Yes Yes Yes
Out-of-Office Replies Yes Yes Yes Yes Yes Yes Yes Yes
Calendar Sharing Yes Yes Yes Yes Yes Yes Yes Yes
Reporting Features and Troubleshooting Tools Exchange Server 2013 Exchange Server 2016 Office 365 Business Essentials Office 365 Business Premium Office 365 Enterprise E1 Office 365 Enterprise E3 Office 365 Enterprise E5 Office 365 Enterprise F1
Microsoft 365 admin center reports No No Yes Yes Yes Yes Yes Yes
Excel Reporting Workbook No No Yes Yes Yes Yes Yes Yes
Web Services Reports No No Yes Yes Yes Yes Yes Yes
Message Trace No Yes Yes Yes Yes Yes Yes Yes
Auditing Reports Yes Yes Yes Yes Yes Yes Yes Yes 3
Unified Messaging Reports Yes Yes No No No Yes Yes No
Sharing and Collaboration Exchange Server 2013 Exchange Server 2016 Office 365 Business Essentials Office 365 Business Premium Office 365 Enterprise E1 Office 365 Enterprise E3 Office 365 Enterprise E5 Office 365 Enterprise F1
Federated Sharing (Including Calendar Publishing) Yes Yes Yes Yes Yes Yes Yes Yes
Site Mailboxes Yes10 Yes10 Yes11 Yes11 Yes11 Yes11 Yes11 Yes11
Public Folders Yes Yes Yes Yes Yes Yes Yes No
Clients and Mobile Devices Exchange Server 2013 Exchange Server 2016 Office 365 Business Essentials Office 365 Business Premium Office 365 Enterprise E1 Office 365 Enterprise E3 Office 365 Enterprise E5 Office 365 Enterprise F1
Outlook for Windows 21 Yes Yes Yes Yes Yes Yes Yes No
Outlook on the web21 Yes Yes Yes Yes Yes Yes Yes Yes
Outlook for Mac21 Yes Yes Yes Yes Yes Yes Yes No
Outlook for iOS and Android21 Yes Yes Yes Yes Yes Yes Yes Yes
Exchange ActiveSync Yes Yes Yes Yes Yes Yes Yes Yes
Mobile Device Management for Office 365 No No Yes Yes Yes Yes Yes Yes
POP and IMAP Yes Yes Yes Yes Yes Yes Yes Yes 12
SMTP Yes Yes Yes Yes Yes Yes Yes Yes
EWS Application support Yes Yes Yes Yes Yes Yes Yes No
Voice Message Services Exchange Server 2013 Exchange Server 2016 Office 365 Business Essentials Office 365 Business Premium Office 365 Enterprise E1 Office 365 Enterprise E3 Office 365 Enterprise E5 Office 365 Enterprise F1
Voice Mail23 Yes Yes No No No Yes Yes No
Integration Between Voice Mail and Third-Party FAX23 Yes Yes No No No Yes Yes No
Third-Party Voice Mail Interoperability23 Yes Yes Yes Yes Yes Yes Yes Yes
Skype for Business Integration Yes Yes Yes Yes Yes Yes Yes Yes
High Availability and Business Continuity Exchange Server 2013 Exchange Server 2016 Office 365 Business Essentials Office 365 Business Premium Office 365 Enterprise E1 Office 365 Enterprise E3 Office 365 Enterprise E5 Office 365 Enterprise F1
Mailbox Replication at Data Centers No No Yes Yes Yes Yes Yes Yes
Deleted Mailbox Recovery Yes Yes Yes Yes Yes Yes Yes Yes
Deleted Item Recovery Yes Yes Yes Yes Yes Yes Yes Yes
Single Item Recovery Yes Yes Yes Yes Yes Yes Yes No
Interoperability, Connectivity, and Compatibility Exchange Server 2013 Exchange Server 2016 Office 365 Business Essentials Office 365 Business Premium Office 365 Enterprise E1 Office 365 Enterprise E3 Office 365 Enterprise E5 Office 365 Enterprise F1
Skype for Business Presence in OWA and Outlook Yes Yes Yes Yes Yes Yes Yes Yes
SharePoint Interoperability Yes Yes Yes Yes Yes Yes Yes Yes
EWS Connectivity Support Yes Yes Yes Yes Yes Yes Yes No
SMTP Relay Support Yes Yes Yes Yes Yes Yes Yes Yes
Exchange Online Setup and Administration Exchange Server 2013 Exchange Server 2016 Office 365 Business Essentials Office 365 Business Premium Office 365 Enterprise E1 Office 365 Enterprise E3 Office 365 Enterprise E5 Office 365 Enterprise F1
Microsoft Office 365 portal access No No Yes Yes Yes Yes Yes Yes
Microsoft 365 admin center access No No Yes Yes Yes Yes Yes Yes
Exchange admin center access Yes Yes Yes Yes Yes Yes Yes Yes
Remote Windows PowerShell access Yes Yes Yes Yes Yes Yes Yes Yes
ActiveSync Policies for Mobile Devices Yes Yes Yes Yes Yes Yes Yes Yes
Usage Reporting Yes Yes Yes Yes Yes Yes Yes Yes
Extending the Service - Customization, Add-ins, and Resources Exchange Server 2013 Exchange Server 2016 Office 365 Business Essentials Office 365 Business Premium Office 365 Enterprise E1 Office 365 Enterprise E3 Office 365 Enterprise E5 Office 365 Enterprise F1
Outlook Add-Ins and Outlook MAPI Yes19 Yes Yes19 Yes19 Yes19 Yes19 Yes19 No

Note

1 Requires an Exchange Online Archiving (EOA) subscription for each on-premises mailbox user that has a cloud-based archive.
2 Azure Information Protection is not included, but can be purchased as a separate add-on and will enable the supported Information Rights Management (IRM) features. Some Azure Information Protection features require a subscription to Office 365 ProPlus, which is not included with Office 365 Business Essentials, Office 365 Business Premium, Office 365 Enterprise E1, Office 365 Education, or Office 365 Enterprise F1.
3 Windows Server AD RMS is an on-premises server that must be purchased and managed separately in order to enable the supported IRM features.
4 Transport rules are made up of flexible criteria, which allow you to define conditions and exceptions, and actions to take based on the criteria. The available criteria and actions differ between Exchange Online, and Microsoft Exchange Server 2013. For a list of available criteria and actions, see the corresponding criteria and actions topics for each product.
5 For Exchange 2013, DLP requires an Exchange Enterprise Client Access License (CAL). For more information about CALs and server licensing, see Exchange Server Licensing.
6 Exchange Server 2013 has most of the same built-in anti-spam capabilities as Exchange Server 2010. For information about the benefits of Exchange hosted spam filtering over the on-premises offerings, see Benefits of Anti-Spam Features in Exchange Online Protection Over Exchange Server 2013.
7 Only accessible via direct access to the Exchange admin center (EAC) management interface.
8 Exchange Server 2013 uses only the Microsoft anti-malware engine. Exchange Online uses multiple anti-malware engines to scan inbound, outbound, and internal messages for malware.
9 An EOA subscription can be purchased separately for each mailbox that requires the inactive mailbox feature.
10 SharePoint must be deployed in the on-premises Exchange organization.
11 SharePoint Online must be included in the Office 365 subscription plan.
12 POP is supported, but IMAP is not.
13 Supported for Exchange Server 2013 on-premises customers who purchase Azure Information Protection. Office 365 Message Encryption requires on-premises customers to route email through Exchange Online, either by using Exchange Online Protection for email filtering, or by establishing hybrid mail flow.
14 Exchange Server 2013 customers need to download and install SP1 in order to access Document Fingerprinting and Policy Tips in OWA and OWA for Devices.
15 BitLocker Drive Encryption is supported for Exchange Server 2013, but an administrator needs to enable the feature.
16 Office 365 Business Essentials, Office 365 Business Premium, and Office 365 Enterprise F1 do not provide access rights for utilization with on-premises servers. To be compliant, customer must purchase or have previously purchased the appropriate CALs or upgrade to an Enterprise SKU that provides these access rights.
17 Connected accounts are supported for POP & IMAP accounts, but disabled for Outlook.com (Hotmail).
18 Using cmdlets in Exchange Online PowerShell to customize the default address lists and the default global address list (GAL) is not supported.
19 Some third-party web parts and add-ins may not be available.
20 For eDiscovery, you need a separate query for on-premises vs. cloud.
21 The table indicates whether or not the client works with the associated plans. It does not mean the clients are necessarily included in the purchase of these plans.
22 For more information, see Controlling your data in Office 365 using Customer Key.
23 Exchange Online UM support for third-party PBX systems via direct connections from customer operated SBCs will end in April 2019. Please see the Exchange team blog Discontinuation of support for Session Border Controllers in Exchange Online Unified Messaging for more information.
24 An F1 user cannot add delegates to their own mailbox, but they can access another mailbox (including shared mailboxes) and perform any actions which have been delegated to them.

Feature availability across Exchange Online standalone plans

Feature Exchange Server 2013 Exchange Server 2016 Exchange Online Plan 1 Exchange Online Plan 2 Exchange Online Kiosk
Planning and Deployment
Hybrid deployment supported Yes Yes Yes Yes Yes23
IMAP migration supported Yes Yes Yes Yes Yes
Cutover migration supported Yes Yes Yes Yes Yes
Staged migration supported No No Yes Yes Yes
Permissions Exchange Server 2013 Exchange Server 2016 Exchange Online Plan 1 Exchange Online Plan 2 Exchange Online Kiosk
Role-Based Permissions Yes Yes Yes Yes No
Role Groups Yes Yes Yes Yes No
Role Assignment Policies Yes Yes Yes Yes No
Message Policy and Compliance Exchange Server 2013 Exchange Server 2016 Exchange Online Plan 1 Exchange Online Plan 2 Exchange Online Kiosk
Archiving Exchange Online-based Mailboxes Yes No Yes Yes No
Cloud-Based Archiving of On-Premises Mailboxes Yes 5 Yes 5 No Yes No
Messaging Records Management (MRM) Retention Tags and Retention Policies Yes Yes Yes Yes Yes
Encryption of data at rest (BitLocker) Yes16 Yes16 Yes Yes Yes
IRM using Azure Information Protection No Yes No11 No11 No11
IRM using Windows Server AD RMS Yes12 Yes12 Yes12 Yes12 Yes12
Office 365 Message Encryption Yes13 Yes13 No11 No11 No11
S/MIME Yes15 Yes15 Yes Yes Yes
In-Place Hold and Litigation Hold Yes Yes No17 Yes No
In-Place eDiscovery Yes22 Yes22 Yes22 Yes22 Yes22
Transport Rules Yes 1 Yes 1 Yes 1 Yes 1 Yes 1
Data Loss Prevention Yes10, 14 Yes10, 14 No Yes No
Journaling Yes Yes Yes Yes Yes
Anti-Spam and Anti-Malware Protection Exchange Server 2013 Exchange Server 2016 Exchange Online Plan 1 Exchange Online Plan 2 Exchange Online Kiosk
Built-In Anti-Spam Protection Yes 2 Yes 2 Yes Yes Yes
Customize Anti-Spam Policies Yes but only via PowerShell Yes but only via PowerShell Yes Yes Yes 8
Built-In Anti-Malware Protection Yes 7 Yes 7 Yes7 Yes7 Yes7
Customize Anti-Malware Policies Yes Yes Yes Yes Yes 8
Quarantine - administrator management Yes Yes Yes Yes Yes 8
Quarantine - end-user self-management No No Yes Yes Yes
Mail Flow Exchange Server 2013 Exchange Server 2016 Exchange Online Plan 1 Exchange Online Plan 2 Exchange Online Kiosk
Custom Routing of Outbound Mail Yes Yes Yes Yes Yes
Secure Messaging with a Trusted Partner Yes Yes Yes Yes Yes
Conditional Mail Routing No No Yes Yes Yes
Adding a Partner to an Inbound Safe List No No Yes Yes Yes
Hybrid Email Routing Yes Yes Yes Yes Yes
Recipients Exchange Server 2013 Exchange Server 2016 Exchange Online Plan 1 Exchange Online Plan 2 Exchange Online Kiosk
Capacity Alerts Yes Yes Yes Yes Yes
Clutter No No Yes Yes Yes
MailTips Yes Yes Yes Yes Yes
Delegate Access Yes Yes Yes|Yes No
Inbox Rules Yes Yes Yes Yes No
Connected Accounts Yes Yes Yes19 Yes19 Yes19
Inactive Mailboxes No No No 6 Yes No 6
Offline Address Book Yes Yes Yes Yes Yes
Address Book Policies Yes Yes Yes Yes Yes
Hierarchical Address Book Yes Yes Yes Yes No
Address Lists and Global Address List Yes Yes Yes20 Yes20 Yes20
Office 365 Groups No No Yes24 Yes24 No
Distribution Groups Yes Yes Yes Yes Yes
External Contacts (global) Yes Yes Yes Yes Yes
Universal Contact Card Yes Yes Yes Yes Yes
Contact Linking with Social Networks Yes Yes Yes Yes Yes
Resource Mailboxes Yes Yes Yes Yes Yes
Conference Room Management Yes Yes Yes Yes Yes
Out-of-Office Replies Yes Yes Yes Yes Yes
Calendar Sharing Yes Yes Yes Yes Yes 18
Reporting Features and Troubleshooting Tools Exchange Server 2013 Exchange Server 2016 Exchange Online Plan 1 Exchange Online Plan 2 Exchange Online Kiosk
Microsoft 365 admin center reports No No Yes Yes Yes
Excel Reporting Workbook No No Yes Yes Yes
Web Services Reports No No Yes Yes Yes
Message Trace No Yes Yes Yes Yes 8
Auditing Reports Yes Yes Yes Yes Yes 8
Unified Messaging Reports Yes Yes No Yes No
Sharing and Collaboration Exchange Server 2013 Exchange Server 2016 Exchange Online Plan 1 Exchange Online Plan 2 Exchange Online Kiosk
Federated Sharing Yes Yes Yes Yes Yes
Site Mailboxes Yes 3 Yes 3 Yes 4 Yes 4 Yes 4
Public Folders Yes Yes Yes Yes No
Clients and Mobile Devices Exchange Server 2013 Exchange Server 2016 Exchange Online Plan 1 Exchange Online Plan 2 Exchange Online Kiosk
Microsoft Outlook Yes Yes Yes Yes No
Outlook Web App Yes Yes Yes Yes Yes
Exchange ActiveSync Yes Yes Yes Yes Yes
POP and IMAP Yes Yes Yes Yes Yes 9
SMTP Yes Yes Yes Yes Yes
EWS Application support Yes Yes Yes Yes No
Outlook for Mac Yes Yes Yes Yes No
Voice Message Services Exchange Server 2013 Exchange Server 2016 Exchange Online Plan 1 Exchange Online Plan 2 Exchange Online Kiosk
Voice Mail Yes Yes No Yes No
Third-Party Voice Mail Interoperability Yes Yes Yes Yes Yes
Skype for Business Integration Yes Yes Yes Yes Yes
High Availability and Business Continuity Exchange Server 2013 Exchange Server 2016 Exchange Online Plan 1 Exchange Online Plan 2 Exchange Online Kiosk
Mailbox Replication at Data Centers No No Yes Yes Yes
Deleted Mailbox Recovery Yes Yes Yes Yes Yes
Deleted Item Recovery Yes Yes Yes Yes Yes
Single Item Recovery Yes Yes Yes Yes No
Interoperability, Connectivity, and Compatibility Exchange Server 2013 Exchange Server 2016 Exchange Online Plan 1 Exchange Online Plan 2 Exchange Online Kiosk
Skype for Business Presence in OWA and Outlook Yes Yes Yes Yes Yes
SharePoint Interoperability Yes Yes Yes Yes Yes
EWS Connectivity Support Yes Yes Yes Yes Yes
SMTP Relay Support Yes Yes Yes Yes Yes
Exchange Online Setup and Administration Exchange Server 2013 Exchange Server 2016 Exchange Online Plan 1 Exchange Online Plan 2 Exchange Online Kiosk
Microsoft Office 365 portal access No No Yes Yes Yes
Microsoft 365 admin center access No No Yes Yes Yes
Exchange admin center access Yes Yes Yes Yes Yes 8
Remote Windows PowerShell access Yes Yes Yes Yes Yes
ActiveSync Policies for Mobile Devices Yes Yes Yes Yes Yes
Usage Reporting Yes Yes Yes Yes Yes
Extending the Service - Customization, Add-ins, and Resources Exchange Server 2013 Exchange Server 2016 Exchange Online Plan 1 Exchange Online Plan 2 Exchange Online Kiosk
Outlook Web App Web Parts Yes Yes Yes Yes Yes
Outlook Add-Ins and Outlook MAPI Yes Yes Yes21 Yes21 No

Note

1 Transport rules are made up of flexible criteria, which allow you to define conditions and exceptions, and actions to take based on the criteria. The available criteria and actions differ between Exchange Online, and Microsoft Exchange Server 2013. For a list of available criteria and actions, see the corresponding criteria and actions topics for each product.
2 For information about the benefits of Exchange hosted spam filtering over the on-premises offerings, see Benefits of Anti-Spam Features in Exchange Online Protection Over Exchange Server 2013.
3 SharePoint must be deployed in the on-premises Exchange organization.
4 SharePoint Online must be included in the Office 365 subscription plan.
5 Requires an Exchange Online Archiving (EOA) subscription for each on-premises mailbox user that has a cloud-based archive.
6 An EOA subscription can be purchased separately for each mailbox that requires the inactive mailbox feature.
7 Exchange Server 2013 uses only the Microsoft anti-malware engine. Exchange Online uses multiple anti-malware engines to scan inbound, outbound, and internal messages for malware.
8 Only accessible via direct access to the Exchange admin center (EAC) management interface.
9 IMAP is not supported.
10 For Exchange 2013 or later, DLP requires an Exchange Enterprise Client Access License (CAL). For more information about CALs and server licensing, see Exchange Server Licensing.
11 Azure Information Protection is not included, but can be purchased as a separate add-on and will enable the supported Information Rights Management (IRM) features. Some Azure Information Protection features require a subscription to Office 365 ProPlus, which is not included with Office 365 Business Essentials, Office 365 Business Premium, Office 365 Enterprise E1, Office 365 Education, or Office 365 Enterprise F1. Office 365 Message Encryption depends on Azure Information Protection.
12 Windows Server AD RMS is an on-premises server that must be purchased and managed separately in order to enable the supported IRM features.
13 Supported for customers running Exchange Server 2013 or later who purchase Azure Information Protection. Office 365 Message Encryption requires on-premises customers to route email through Exchange Online, either by using Exchange Online Protection for email filtering, or by establishing hybrid mail flow.
14 Customers running Exchange Server 2013 or later need to download and install the latest cumulative update (CU), or the immediately previous CU, to access Document Fingerprinting and Policy Tips in OWA and OWA for Devices.
15 Available to customers running Exchange Server 2013 or later.
16 BitLocker Drive Encryption is supported for Exchange Server 2013, but an administrator needs to enable the feature.
17 Exchange Online Plan 1 has a size limit on the mailbox and archive. Exchange Online Archiving for Exchange Online add-on adds unlimited cloud-based archive and In-Place Hold.
18 Exchange Online Kiosk calendars can only be accessed or shared through OWA.
19 Connected accounts are supported for POP & IMAP accounts, but disabled for Outlook.com (Hotmail).
20 Using cmdlets in Exchange Online PowerShell to customize default address lists and the default global address list (GAL) is not supported.
21 Some third-party web parts and add-ins may not be available.
22 For eDiscovery, you need a separate query for on-premise vs. cloud.
23 Exchange Online Kiosk does not provide access rights for utilization with on-premises servers. To be compliant, customer must purchase or have previously purchased the appropriate CALs or upgrade to an Enterprise SKU that provides these access rights.
24 Office 365 Groups is available with reduced functionality.