UX & product certifications
- Nielsen Norman Group UX Certified (UXC #1045574)
- Professional Scrum Master I
- Certified Scrum Product Owner (Scrum Alliance)
- Member, Project Management Institute (PMI)
About
A UX leader who has done every part of the job.
Researcher, information architect, designer, product owner, manager — 18+ years turning complex digital products into experiences people trust.
About Matthaios Mantzios
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Matthaios Mantzios
Founder, UXellence · UX Design Leader
NN/g UX CertifiedScrum Product OwnerAuthor
The short version
Nearly two decades, every role in UX.
Matthaios Mantzios is a UX leader who has spent nearly two decades building human-centred digital products in fast-paced, engineering-led environments.
He has led UX teams, owned products used by millions, and guided organizations through change — pairing strategic direction with hands-on craft. As a Scrum Product Owner, he became known for translating complex technical detail into clear business terms and building consensus among senior stakeholders and executive leadership.
That range — researcher, architect, designer, product owner, manager — is what UXellence brings to every engagement: one senior partner who connects research, strategy, design and delivery into a single, accountable thread. For larger programs, Matthaios draws on a trusted network of specialists, staying hands-on as the lead throughout.
Career
A track record across scale and sectors
Head of UX & Design — present
Built a remote-first UX/UI practice from the ground up, raising UX maturity across an engineering-led organization and serving institutions including the University of Cambridge Judge Business School, Cambridge University Press and the European Environment Agency.
Scrum Product Owner — digital identity
Owned the vision for a telecom's authentication and profiling platform serving 5M+ user accounts and daily logins — the backbone of an ecosystem of sites and apps.
UX Team Leader & UX Expert
Led UX designers and researchers, developed research-based UX strategies, and drove a group-wide digital brand merge recognized as a Deutsche Telekom group case study — lifting web-touchpoint satisfaction to an all-time-high 94%.
Project & Web Projects Manager
Delivered self-service and billing products with measurable impact: 90% payment satisfaction, 40% fewer overdue payments, 95% e-billing satisfaction — grounded in PMI-based planning.
Credentials
Certified expertise, formal foundations
Education
- M.Sc. Mechanical Engineering — University of Arizona (Reliability & Quality; fellowship & scholarship)
- Mechanical & Industrial Engineering Diploma — University of Thessaly (5-year program)
Continuous learning
- Multiple NN/g courses: UX & analytics, usability, mobile UX
- Design Thinking for Innovation — University of Virginia
- Front-end & responsive design — University of Michigan
Thought leadership
Sharing what works with the wider field.
Beyond client work, Matthaios is an active voice in the UX community.
He writes about the evolving UX landscape — from AI's impact on design to inclusive UX strategy — for outlets including UX Planet, Fast Company and The Decision Lab, and publishes regularly on Medium.
He is the author of Web and Mobile Accessibility: A Comprehensive Guide to WCAG 2.2, the ADA, and the European Accessibility Act (Second Edition) — a practical guide to WCAG 2.2, the ADA, Section 508 and the European Accessibility Act, available on Amazon — and mentors emerging designers on ADPList.
Standards work
Matthaios is Greece's delegated expert in CEN-CENELEC JTC 21 Working Group 4, "Foundational and societal aspects", appointed in September 2026 on the nomination of ELOT, the national standards body. The working group develops the European standards behind the EU AI Act's requirements for logging, transparency, human oversight, accuracy and robustness.
Featured in & on
UX Planet
Fast Company
The Decision Lab
Amazon · Author
ADPList · Mentor
Industries served
- Telecom & digital identity
- Financial services & insurance
- Publishing & media
- Higher education & academia
- Public sector
Let's build something worth using.
Whether you need a fresh perspective, a research partner or senior design leadership, UXellence is ready to help.
Get in touch