C5 Alliance

St Peter Port

About

C5 Alliance is an IT consultancy, part of the C5 group, and is ISO 27001 certified. The firm specialises in Microsoft platform consultancy, holding five of Microsoft's six Solutions Partner designations. Services include managed IT with SLA-backed support and 24x7x365 monitoring. C5 Alliance serves clients in trust and fund, banking, utilities, education, and government sectors, including the States of Guernsey staff IT helpdesk from August 2025. Chris Ash is the Managing Director for Guernsey. —

Quick facts

Legal form: Part of the C5 group; described by C5 as the sister technology business to BDO Jersey
Industries served: Trust and fund, banking, utilities, education, government
Specialises in: Microsoft platform consultancy; holds five of Microsoft's six Solutions Partner designations

People3

Chris Ash
Managing Director
Guernsey

Services offered

Managed IT services with SLA-backed support and 24x7x365 performance monitoring
States of Guernsey staff IT helpdesk
from 1 August 2025 under a two-year agreement

Credentials

Qualifications

ISO 27001 certified since 2018 (recertified 2024)

Hours

Mon: 9:00 AM – 5:00 PM
Tue: 9:00 AM – 5:00 PM
Wed: 9:00 AM – 5:00 PM
Thu: 9:00 AM – 5:00 PM
Fri: 9:00 AM – 5:00 PM
Sat: Closed
Sun: Closed

Contact

Phone: +44 1481 812345
Email: enquiries@c5alliance.com
Website: www.c5alliance.com
Address: No. 1 The Plaza, Elizabeth Avenue, St Peter Port, Guernsey, GY1 2HU

Location

Directions ↗

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