Senior UX/UI Designer (CRO)

VML, part of WPP, is a leading creative company that combines brand experience, customer experience, and commerce, creating connected brands to drive growth. VML is celebrated for its innovative and human first, award-winning work for blue chip client partners including AstraZeneca, Colgate-Palmolive, Dell, Ford, Microsoft, Nestlé, The Coca-Cola Company, and Wendy's.

We are seeking a highly skilled and passionate UX/UI or Product Designer with a specialized focus on Conversion Rate Optimisation (CRO) and experimentation to join our dynamic, flexible team, embedded directly within our dedicated CRO squad. This hybrid role is for a hands‑on designer who excels at crafting, optimizing, and delivering high‑performing digital experiences across desktop and mobile.

You will design premium web experiences and landing pages that drive user engagement, maximize conversions, and seamlessly support business growth. You will be instrumental in translating user data, behaviour analytics, and strategic hypotheses into high‑impact design variations and optimized user journeys.

Working collaboratively within a cross‑functional CRO squad, you will be responsible for the end‑to‑end design lifecycle of A/B and multivariate tests, ensuring every design is both meticulously executed and strategically optimized for maximum performance.

What you’ll be doing

• Lead the end‑to‑end UX/UI design process for A/B testing, multivariate testing, landing pages, and ongoing Optimisation initiatives across web and mobile platforms.
• Develop detailed user flows, interaction models, wireframes, and interactive, high‑fidelity prototypes specifically optimized for experimentation and user validation.
• Create pixel‑perfect UI designs that respect and elevate our clients' brand guidelines, utilizing persuasive design patterns, psychological triggers, and clear, conversion‑focused hierarchies.
• Work with and support tokenized design systems (DS), ensuring scalability, efficiency, and consistency of components across a multi‑brand environment.
• Design and optimize unique, tailored user journeys for our client's portfolio of sub‑brands, ensuring sub‑brand visual identities and unique experiences are maintained while adhering to core design system architectures.
• Focus on landing page layouts, micro‑interactions, persuasive copywriting placement, and checkout/signup funnel Optimisation to systematically minimize friction.
• Translate user feedback, testing data, and statistical results from A/B tests into actionable, iterative design recommendations.
• Ensure all experiment designs are technically feasible and collaborate closely with developers during implementation, providing detailed specifications and reviewing builds to ensure high‑fidelity execution of tests.

Collaboration & CRO Advocacy

• Work closely with CRO Strategists, Web Analysts, Product Managers, and front‑end Developers in a fast‑paced, agile squad environment to manage multiple experimentation pipelines.
• Advocate for data‑informed, evidence‑based design decisions, presenting design concepts and experimentation rationale clearly to clients and stakeholders to build alignment.
• Actively contribute to and maintain conversion‑oriented design libraries, templates, and documented best practices to scale our Optimisation efforts.

What we want from you

• Experience designing for A/B testing, personalisation, CRO, or landing page optimisation would be a bonus, particularly where design decisions have been informed by user insight, performance data, or test learnings.
• Deep understanding of working with and leveraging tokenized design systems (design tokens in Figma) to manage styling variables, thematic brand changes, and cross‑platform consistency efficiently.
• Proven ability to design distinct and unique user journeys for a client's various sub‑brands, striking the perfect balance between brand customization and core systemic rules.
• Experience designing high‑converting experiences for e‑commerce, transactional websites, lead‑generation pages, or digital products is highly desirable.
• A must‑have portfolio showing a clear end‑to‑end design process, specifically highlighting how you use user insights, data, or test hypotheses to design landing pages, optimized user flows, and successful A/B test variations.
• Deep understanding of user psychology, persuasive design, usability standards, responsive layouts, and platform‑specific UX/UI guidelines.
• Exceptional proficiency in Figma, with the ability to create structured, scalable design files, component libraries, and realistic prototypes for testing.
• Solid understanding of front‑end capabilities (HTML, CSS, and basic JavaScript limitations) to ensure your Optimisation designs are technically feasible and performant.
• Strong communication skills, with a collaborative mindset, comfortable presenting design rationale to stakeholders and working in fast‑paced agile development/testing cycles.
• Strong understanding of web accessibility (WCAG) and page performance considerations to design fast, inclusive, and seamless experiences.

What we can offer you

Alongside the opportunity to work with some of the most exciting brands around the world, we’ll also prioritise your career development and help you grow your skills. We’ll empower you to make a difference, allow you to be yourself, and respect who you are. We offer a great benefits package including a discretionary bonus scheme, training opportunities, competitive pension, medical insurance, life assurance, social events, opportunities to buy and sell holidays, family friendly policies, discounts with hundreds of retailers and much more.

Our culture thrives on our core values, designed for impact‑driven individuals: Heart, Brains and Courage. We lead with Heart, fostering empathy and trust where genuine connections and human‑centric work flourish. We empower your Brains for innovation, valuing relentless curiosity and collaborative intelligence to solve complex challenges. And we champion Courage, inspiring you to speak up, embrace experimentation, and advocate for bold solutions that push our thinking to be better than yesterday.

WPP (VML) is an equal opportunity employer and considers applicants for all positions without discrimination or regard to characteristics. We are committed to fostering a culture of respect in which everyone feels they belong and has the same opportunities to progress in their careers.