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

MMMatthaios Mantzios, Founder of UXellence

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.

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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

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)

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.

Book cover — Web and Mobile Accessibility, Second Edition, by Matthaios Mantzios

Second Edition — WCAG 2.2 · ADA · Section 508 · EAA

View on Amazon

All formats & full contents →

Featured in & on

UX Planet Fast Company The Decision Lab Amazon · Author ADPList · Mentor

Industries served

  • Telecom & digital identity
  • Publishing & media
  • Public sector & academia

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