Retirement of Exchange Web Services in Exchange Online

Platinum Contributor

Sep 19, 2023

Update 3/27/2025: We updated the "Access to public folders" section below.

This post is a part of our EWS (Exchange Web Services) to Microsoft Graph Migration Guide Series.

In 2018, we announced that we were no longer making feature updates to Exchange Web Services (EWS) in Exchange Online, and we advised developers to move to Microsoft Graph.

Today, we are announcing that on October 1, 2026, we will start blocking EWS requests to Exchange Online.

While the EWS components of the service will continue to receive security updates and certain non-security updates, product design and features will remain unchanged. This change also applies to the EWS SDKs for Java and .NET, as well.

Despite today’s announcement, EWS is still available and supported for use in production environments. But we strongly suggest migrating to Microsoft Graph to access Exchange Online data and gain access to the latest features and functionality.

Today’s announcement and the retirement of EWS apply only to Microsoft 365 and Exchange Online (all environments); there are no changes to EWS in Exchange Server. EWS will continue to be fully supported for Exchange on-premise mailboxes.

Migrating Applications to Microsoft Graph

We know there are several feature gaps between EWS and Microsoft Graph, and though the list below is not exhaustive, these are the gaps most frequently reported to us by developers:

Access to Archive Mailboxes – We are working on delivering access to archive mailboxes via Microsoft Graph and will provide an updated timeline in the coming months.
Folder Associated Information / User Configuration – We are working on these features and will provide an updated timeline in the coming months.
Exchange Online Management – We are investigating solutions for this and will provide an updated timeline in the coming months.
Access to Public Folders – After evaluating the usage of public folders, we have decided to restrict programmatic access to public folders to supported Outlook clients only, and for bulk import/export purposes. We will not provide APIs for programmatically creating, reading, updating and deleting public folders after October 2026 (also see Security Related Updates in Exchange Online).

We know there are other gaps not listed above, and we continue to work on closing them, but it’s possible some functionality will not make it to Microsoft Graph. We encourage you to provide feedback to us, keep a close eye on the What’s new in Microsoft Graph page, and explore alternatives for functionality or features not available in Microsoft Graph.

Next Steps

The retirement of these APIs follows our service deprecation policies. We understand changes like this may cause some inconvenience, but we are confident it will ensure more secure, reliable, and performant experiences.

We will publish regular communications as we progress towards this deadline to aid affected tenants in identifying EWS usage. We encourage all customers to monitor Message Center and this blog for related content.

Thank you in advance for updating and opening your apps to a wider range of useful and intelligent features on Microsoft Graph. We are extremely excited about the growing opportunities that Microsoft Graph offers to developers, and we remain fully committed to our journey to empower developers to access Microsoft 365 data with the most modern features and tools.

The Exchange Team

Updated Mar 27, 2025

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60 Comments

luberth
Microsoft
Sep 19, 2023
Last time we talked about this, we communicated no more features were going to be added to EWS (instead, any new functionality was going to be added to Microsoft Graph). This time, answering your question VasilMichev et al., we spent a couple of semesters analyzing EWS telemetry and meeting third-party developers to not only identify gaps and understand business cases behind the feedback received by the community/ISVs, but also to prioritize the effort to close these gaps and plan their implementation with the engineering teams.

So yes, we are already addressing many of these. We will update this same thread when major features hit either beta or v1 endpoints.
probich0
MVP
Sep 19, 2023
While we're at it, I want to echo what Vasil, Peter, and Michel have said: we have been waiting for years to get functionality parity in Graph as an EWS replacement. Removing EWS capability is going to cause major problems for our customers-- in my case, I don't want to have to tell them "oh, sorry, we can't back up public folders any more" (to cherry-pick one example) but killing EWS without replacing its functionality is going to lead to that.
cengizyilmaz
MCT
Sep 19, 2023
It's a very early decision for Ews to retire.
Peter Kozak
Brass Contributor
Sep 19, 2023
I echo the concerns raised by @Vasil Michev and MichelZCF about the feature gaps between EWS and Microsoft Graph. These gaps have been pointed out by the community for years, yet we haven't seen considerable progress in addressing them. Announcing the retirement of EWS without a clear roadmap to achieve feature parity seems premature and, frankly, very concerning.

My question to Microsoft is: Will customers and partners end up with a premium (paid per API call) Graph to achieve similar functionality to EWS?
MichelZCF
Brass Contributor
Sep 19, 2023
I would like to tout the same horn as VasilMichev.. we have been pointing out deficiencies in the "replacements" for EWS for years... without any movement. How is this time going to be different? How can you announce a retirement without even having the plans to provide parity? This is, as we like to say, "suboptimal".
VasilMichev
MVP
Sep 19, 2023
Those same gaps have been repeatedly brought by the community/ISVs since the original "deprecation" notice, yet 5 years later we've seen zero movement on that front. Are you actually going to address them?

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Retirement of Exchange Web Services in Exchange Online