Azure Email Retires in 2028 With No Microsoft Option for Customer Mail

Microsoft will retire Azure Communication Services Email on Sept. 30, 2028, the company said in its September 2026 “What’s new” entry for the service. That day Azure Communication Services ends as a standalone offering. Email is one of 11 services on the retiring list. SMS, WhatsApp messaging, Chat and Rooms are also on it.

Maintenance mode starts now

ACS Email gets “security and critical fixes only” until it retires, according to Microsoft’s retirement and breaking changes guide, last updated Sept. 24. The guide says the team is “not able to commit to new feature development.” Verified sending domains keep working until the retirement date. Quota increase requests will be “handled on a case-by-case basis.”

New customers can still create ACS Email resources, but Microsoft says that “is subject to change at any time.” It recommends “using the two-year retirement period to migrate existing workloads off ACS Email rather than onboarding new solutions.”

Microsoft’s own option sends only inside a tenant

Microsoft 365 High Volume Email, the in-house alternative the guide names first, sends only to recipients inside the sender’s own Microsoft 365 tenant, the guide’s comparison table shows. ACS Email reaches internal and external recipients through a REST API, SDKs and SMTP. High Volume Email starts with SMTP only, with “SDK support planned.” It allows 50 recipients per message and requires Microsoft 365 licensing.

The guide lists Exchange Online “for reference” and says it is “designed for user mail, not bulk.” For application email to outside recipients, it points to two third-party providers on Microsoft Marketplace, Infobip and Telesign. Some of those offers may count toward a customer’s Azure spending commitment, the guide says.

Key takeaways

• ACS Email retires Sept. 30, 2028, per Microsoft’s September 2026 “What’s new” entry.
• Until then it gets security and critical fixes only.
• New sign-ups are allowed for now. Microsoft says that can change at any time.
• Microsoft’s in-house alternative sends only within a tenant. For external mail, the guide names Infobip and Telesign.

The take

We think the most important line in Microsoft’s guide is the “Recipients” row of its comparison table. Teams used ACS Email to send receipts, password resets and sign-up confirmations to their customers. The Microsoft product offered in its place sends mail only inside an organization. For the main job ACS Email did, Microsoft has no product of its own to move to. Teams face a vendor search, not a migration.

Two years sounds like plenty of time. But a new sending setup needs time to earn trust with mailbox providers. Microsoft’s own guide gives ACS Email customers ramp-up guidance of two to four weeks. We’d expect any new provider to ask for a similar warm-up. Teams should list every app that sends through ACS Email today, choose a provider and start warming a new sending domain well before 2028.