Microsoft has migrated 63,000 users at the UK's Home Office to Teams Phone in just eight days.
In a tremendously impressive digital transformation project, the Redmond-based vendor collaborated with Colt and Netcompany to introduce Microsoft Teams Phone to the Home Office department of the UK government, intending to modernise its communications infrastructure.
The Home Office affirms that the transformative initiative, combined with the full adoption of Microsoft 365 E5, has boosted productivity, enhanced collaboration, strengthened security, and empowered the Home Office to deliver more efficient public services.
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The Challenge
Seamless communication is vital to the Home Office’s national security and public safety operations. Managing nearly one billion call and conference minutes annually—60 percent with video—the department relies on a robust network for real-time decision-making and collaboration.
"Our communication infrastructure is the backbone of our operations," said Robbie Warwick, Head of the Voice and Video Products at Home Office. "It ensures we can respond swiftly to challenges and collaborate effectively across all areas of responsibility."
Our service users can be in life-threatening situations, so it's vital we get it right. When technology operates seamlessly—so much so that no one notices—it means it's working."
In 2018, the Home Office partnered with Microsoft to upgrade its communications by adopting Skype for Business, signalling a key step in strengthening its operational resilience. For four years, the Skype for Business service—delivered with Colt and its third-party supplier—supported the department’s telephony needs, streamlining comms and reinforcing the Home Office's partnership with Microsoft.
Building on this success, the Home Office sought further innovation within Microsoft’s ecosystem. This led to the next strategic step: a complete transition to Microsoft Teams Phone.
Since 2020, Microsoft Teams has been used primarily for collaboration in Islands mode, while Skype for Business remained the core telephony solution. The Home Office prioritised migration to consolidate licensing, streamline infrastructure, and eliminate redundancy. This shift also supported the upgrade to Microsoft 365 E5, unlocking enhanced security, compliance, and operational efficiencies.
"With Microsoft Teams Phone, we saw immense potential to transform the way we worked, creating a more unified and adaptable environment for collaboration," said Robbie Warwick.
The Transformation Project in Detail
As outlined, the Home Office took a bold approach to its Microsoft Teams Phone transition, prioritising speed and precision over a gradual rollout. Instead of a phased migration, the team executed a meticulously planned switch in just eight working days, minimising disruption while maintaining operational security and ensuring uninterrupted essential services.
"By tackling everything at once and focusing our resources on a quick resolution, we aimed to deliver the highest quality service to users," Warwick explained. "We weren’t going to run systems side by side, as delaying would only prolong the complexity associated with the change for users. Instead, we prioritised automation and speed, ensuring the change-effort stayed within the technology teams."
The migration began with a pilot involving 500 users to identify potential issues and refine the strategy. After its success, the process accelerated rapidly. The first wave transitioned 500 users, followed by a two-day pause for assessment. Then, 10,000 users were migrated in a single night, with a break day before ramping up to 20,000 users per night for three consecutive nights. The entire transition was completed within a week.
