Developing a digital and sustainable world together

Digital services and technology consulting

About SII UK

SII UK is a specialised provider of software, systems, manufacturing and electronic engineering, project management, and IT services with a focus on the aerospace, defence and space domains but also covering transportation and energy. We cover the length and breadth of the UK.

Celebrating our 10th anniversary in 2025, we're proud to be part of the global SII Group, which brings over 40 years of industry expertise to our operations.

Our Mission
At SII UK, our mission goes beyond conventional engineering services. We develop sophisticated information and mission systems that form the backbone of critical operations in aerospace, defence and space. We're passionate about contributing to the design and development of future products and services that advance our clients' capabilities and strategic objectives.

Our Key figures

£8.9M

2025/26 Revenue

110+

Employees

What We Do

Our team of expert engineers deliver tailored solutions in:

System Engineering
Software Engineering
Electronic Engineering
Information Technology Services
Project Management
Manufacturing Engineering
Mechanical Engineering
Electrical Engineering

Collaborateurs de l'agence SII Nouvelle Aquitaine

What sets us apart

We combine technical expertise with deep industry knowledge to deliver solutions that address complex challenges. Our engineering approach focuses on creating robust, scalable, and secure systems that meet the exacting standards of defence and space applications.

Through collaborative partnerships with our clients, we aim to be more than just a service provider—we strive to be a trusted advisor and innovation partner. We're committed to understanding the unique requirements of each project, enabling our clients to achieve their missions while preparing them for future technological advancements.

By delivering exceptional technical solutions, we help our clients maintain their competitive edge and operational excellence in environments where precision, reliability, and security are paramount.

1 minute to discover Let's Tech Together

Discover our commitments

Didier Bonnet

International Director Groupe SII

Antoine Leclercq

International Director Groupe SII

At SII UK, we are driven by a shared vision of delivering exceptional value to our clients, fostering an inclusive and collaborative work culture, and being leaders in innovation delivering engineering services. As the Managing Director of SII UK, I am proud to be part of a company that continually sets itself apart through its commitment to excellence, quality, and operational efficiency. Our company motto, "Be Ambitious," reflects our approach to every project and challenge. We continuously push boundaries to deliver exceptional results for our clients. While celebrating a decade of excellence in the UK, we leverage the strength, resources, and knowledge of our global parent company, bringing international best practices and half a century of experience to every engagement.