Senior UX/UI Designer (CRO)

VML; Greater London; Hybrid; GBP 60,000 - 90,000; Full time

Benefits offered by this job

Discretionary bonus

Training opportunities

Medical insurance

Life assurance

Competitive pension

Social events

Employee discounts

Family-friendly policies

Job summary

VML is seeking a highly skilled UX/UI or Product Designer with a CRO focus to join our hybrid CRO squad in London. This hands-on role drives conversion through design across desktop and mobile, translating data and hypotheses into testable experiences.

You will own end-to-end design for A/B and multivariate tests, develop flows, wireframes, and high-fidelity prototypes, and collaborate with developers to ensure pixel-perfect execution that respects brand guidelines.

Qualifications

• Portfolio demonstrating end-to-end design for landing pages and experiments.
• Experience with A/B and multivariate tests and data-driven design decisions.
• Strong knowledge of tokenised design systems.
• Experience in e-commerce or lead-generation websites.

Responsibilities

• Lead end-to-end UX/UI design for A/B and multivariate tests.
• Create detailed user flows, wireframes, and high-fidelity prototypes for experimentation.
• Design pixel-perfect UI aligned with brand guidelines and persuasive patterns.
• Collaborate with tokenised design systems across multiple brands.
• Plan user journeys for sub-brands while maintaining core system rules.
• Translate test results into actionable design changes.
• Ensure designs are technically feasible with frontend developers.

Skills

UX design

CRO

A/B testing

Multivariate testing

Figma

Prototyping

Design systems

HTML/CSS basics

Collaboration

Accessibility

Tools

GA / Analytics tools

Job description

Who We Are

VML is a global creative company that combines brand experience, customer experience, and commerce to create connected brands that drive growth. Guided by a Human First philosophy, VML is known for its innovative work for brands and consistently ranks among the world’s leading creative companies, including the WARC Creative 100. VML’s global network spans 55+ markets with principal offices in Buenos Aires, Kansas City, London, New York, São Paulo, Shanghai and Singapore.

VML is part of WPP, the trusted growth partner for the world's leading brands. Powered by exceptional talent and our agentic marketing platform WPP Open, WPP unites cutting-edge media intelligence and data solutions, creativity, production, enterprise solutions and expert strategic counsel.

For more information, please visit www.vml.com and follow along on LinkedIn #WeAreVML.

The opportunity

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, maximise 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 optimised for maximum performance.

What you’ll be doing

You are a hands‑on, highly motivated, and self‑sufficient UX/UI or Product Designer with deep expertise in conversion‑centered design principles, web/mobile usability, and data‑driven Optimisation. Your passion for user‑centric design pushes you to create intuitive, efficient, and visually stunning digital experiences that perform.

Conversion‑Centered Design & Execution

• 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 optimised 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 tokenised design systems (DS), ensuring scalability, efficiency, and consistency of components across a multi‑brand environment.
• Design and optimise 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 minimise 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

• Desirable: 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.
• Tokenised Design Systems (DS) Mastery: Deep understanding of working with and leveraging tokenised design systems (design tokens in Figma) to manage styling variables, thematic brand changes, and cross‑platform consistency efficiently.
• Multi-Brand Navigation: 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.
• Digital Commerce & Product Context: Experience designing high‑converting experiences for e‑commerce, transactional websites, lead‑generation pages, or digital products is highly desirable.
• Exceptional Portfolio: 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, optimised user flows, and successful A/B test variations.
• Mastery of UX & Conversion Principles: Deep understanding of user psychology, persuasive design, usability standards, responsive layouts, and platform‑specific UX/UI guidelines.
• Figma & Prototyping Proficiency: Exceptional proficiency in Figma, with the ability to create structured, scalable design files, component libraries, and realistic prototypes for testing.
• Technical Understanding: Solid understanding of front‑end capabilities (HTML, CSS, and basic JavaScript limitations) to ensure your Optimisation designs are technically feasible and performant.
• Collaboration & Agility: Strong communication skills, with a collaborative mindset, comfortable presenting design rationale to stakeholders and working in fast‑paced agile development/testing cycles.
• Accessibility & Performance: 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.

Permanent Only

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.

How We Use AI In The Recruitment Process

To ensure more focused and engaging conversations, we leverage AI in our recruitment processexclusively for secure, objective note‑taking, never for evaluative judgments. This allows our team to be fully present with you. You are always welcome torequest a transcript of these notes or opt outof this feature at any time. Opting out will not impact the outcome of the interview process.

We believe the best work happens when we're together, fostering creativity, collaboration, and connection. That's why we’ve adopted a hybrid approach, with teams in the office an average of four days a week. If you require accommodations or flexibility, please discuss this with the hiring team during the interview process.

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.