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CASE STUDY The National Health Service (NHS)

NHSMail migration to Microsoft Exchange Online

NHSmail: World’s largest email migration to the cloud


Call for change

The National Health Service (NHS) cares for more than one million patients every 36 hours. So, when the COVID-19 crisis erupted, NHS support was more vital than ever before.

The NHS’s frontline healthcare workers needed the best digital messaging tools to work together even faster and more collaboratively. Accessing the latest cloud-based communication technologies would help frontline staff communicate more effectively and improve patient care.

However, equipping all NHS employees with the leading digital collaboration innovations during the pandemic was no small feat. The undertaking required moving 2.1 million NHS mailboxes to Microsoft’s Exchange Online platform in record time.

When tech meets human ingenuity

This mass-scale project was undertaken in partnership with NHS Digital, Avanade and Microsoft. The outcome? A robust cloud-based framework that meets the collaboration challenge while helping the NHS better address the UK’s healthcare needs.

Accenture supported an organisation-wide Microsoft Teams implementation. In seven days the integration of the chat, call and video meeting tool was built and rolled out to 1.2 million NHS employees.

Next came the move to the cloud. Approximately 22,000 NHSmail accounts were converted to the cloud each evening and 83,000 accounts every weekend, a tremendous achievement amidst the backdrop of COVID-19.

The migration of NHSmail to Exchange Online has enabled us to provide staff across the NHS with a mail system which is functionally richer, more secure and lower cost.

Sarah Wilkinson / former NHS Digital Chief Executive

A valuable difference

With the Teams, O365 and Online Exchange systems in harmonious operation across the organization—and 2.1 million mailboxes migrated—the NHS can now conduct secure patient consultations via audio and video calls on a national scale. And they can do this while maintaining employee safety, enabling service continuity, creating additional capacity and improving provider and patient experiences.

Local NHS organizations now have access to the full Virtual Visits capability, using the Microsoft Teams Bookings app across individual institutions. On top of having a centralized view of virtual appointments and patient capacity, practice managers and IT leaders can also enable Virtual Visits.

The numbers


of data copied to the cloud

700k +

support site hits on migration content


mailboxes migrated

< 1.2%

users who required support

We are incredibly proud to help the NHS and its essential front-line workers use the very best digital tools available to respond to the COVID-19 crisis.

Julie Sweet / Accenture Chair & CEO