Lead Systems Administrator Windows - Non-Profit

Client Server Limited; Greater London; Hybrid; GBP 45,000 - 55,000; Full time

Benefits offered by this job

25 days holiday

Employee Assistance Programme

Cycle to work scheme

Gym and retail discount platform

Training and career development

Job summary

Client Server Limited is seeking a hands-on Lead Systems Administrator (Windows O365 Security) to own IT infrastructure for a charity, spanning London offices and remote working across the UK. You will head two System Administrators, balancing technical delivery with team development.

You’ll manage Entra ID, Intune, SharePoint and Teams, plus Windows and Android devices, ensuring reliable backups and disaster recovery. Strong security focus with Defender and Purview is essential.

Qualifications

• Hands-on experience with Microsoft 365 suite and Entra ID.
• Experience managing Windows and Android devices across multiple sites.
• Strong networking and troubleshooting skills with external suppliers.
• Familiarity with Microsoft security tools (Defender).
• Understanding of backup, disaster recovery and vulnerability management.
• Proven experience leading or developing a small IT team.

Responsibilities

• Lead and develop a small technical team while focusing 70% on technical delivery.
• Own and operate the charity's IT infrastructure across multiple sites and offices.
• Manage cloud-based Microsoft 365 environment, devices and licensing.
• Improve security posture with Defender, Purview and policy enforcement.
• Collaborate with stakeholders to document processes and drive automation.

Skills

Microsoft 365

Entra ID

Intune

SharePoint

Teams

Windows devices

Android devices

Networking

Security tools

Data protection basics

Tools

Microsoft Defender

Purview

Job description

Lead Systems Administrator (Windows O365 Security) London /WFH to £50k

Are you a hands‑on IT professional with strong Microsoft 365 and infrastructure experience, looking to combine technical ownership with team leadership in a purpose-driven organisation?

You could be progressing your career, taking ownership of the IT infrastructure for a charity that enables waste food distribution across the UK to those in need.

As a Lead Systems Administrator you'll take responsibility for the systems, devices and infrastructure supporting colleagues across offices and warehouses. Reporting to the Senior Technology Services Manager, you'll lead two System Administrators, spending around 70% of your time on technical delivery and 30% leading and developing the team.

You'll manage the organisation's cloud-based Microsoft 365 environment, including Entra ID, Intune, SharePoint and Teams, alongside Windows laptops, Android warehouse devices and the infrastructure supporting warehouse operations. You'll troubleshoot network and connectivity issues, oversee suppliers, manage user access and licensing and ensure reliable backup and disaster recovery arrangements.

You'll also maintain and improve security across the technology estate, managing Microsoft Defender and Purview, leading Cyber Essentials certification, overseeing vulnerability remediation and responding to security incidents. As the organisation explores AI tools such as Microsoft Copilot, you'll help ensure these are adopted safely, with appropriate access controls and data protection measures.

Working closely with the Service Manager and wider technology team, you'll act as the technical escalation point, improve processes through automation and provide practical advice to senior stakeholders. You'll also maintain technical documentation, strengthen operational processes and help your team develop their skills.

Location / WFH:

You can work from home most of the time, the Charity have five office sites across London, you could go to any of them but will only be required in once a month.

About you:

• You have strong hands‑on experience with Microsoft 365, Entra ID, Intune, SharePoint and Teams
• You have experience managing Windows and Android devices across multiple sites
• You have good networking and troubleshooting skills, including working with external suppliers
• You have experience with Microsoft security tools e.g. Defender
• You have an understanding of backup, disaster recovery, vulnerability management and data protection
• You have experience leading or developing a small technical team
• Ideally you will have a recognised security qualification, such as CompTIA Security+, CISSP or CISM.
• You have a proactive, methodical approach, with strong communication skills and the ability to explain technical issues clearly

What's in it for you:

As a Lead Systems Administrator you will earn a competitive package:

• Salary to £50k
• 25 days holiday (increasing to 30 over time) plus your birthday off
• Employee Assistance Programme including 24 hour GP helpline
• Cycle to work scheme
• Gym and retail discount platform
• Continuous training and career development opportunities