Senior UX/UI Designer (CRO)

📍 Job Overview

Job Title: Senior UX/UI Designer (CRO)

Company: VML

Location: London, England, United Kingdom

Job Type: Full-time

Category: UX/UI Design & Conversion Rate Optimization (CRO)

Date Posted: 2026-09-16

Experience Level: Mid-Senior (5-10 years)

Remote Status: Hybrid

🚀 Role Summary

• Lead end-to-end UX/UI design for A/B and multivariate testing initiatives within a dedicated CRO squad.

• Develop high-fidelity designs and prototypes optimized for experimentation and user validation across desktop and mobile platforms.

• Leverage user data, behavior analytics, and strategic hypotheses to create impactful design variations and optimize user journeys for maximum conversion.

• Collaborate closely with CRO Strategists, Web Analysts, Product Managers, and front-end Developers in a fast-paced, agile environment.

• Design premium web experiences and landing pages that drive user engagement, maximize conversions, and support business growth.

📝 Enhancement Note: This role is positioned as a Senior UX/UI or Product Designer with a strong specialization in Conversion Rate Optimization (CRO). The emphasis on "embedded directly within our dedicated CRO squad" suggests a highly collaborative, agile environment focused on iterative design and data-driven decision-making, rather than traditional agency client management. The hybrid work model and specific mention of 4 days in office per week indicates a structured approach to in-person collaboration.

📈 Primary Responsibilities

• Lead the end-to-end UX/UI design process for A/B testing, multivariate testing, landing pages, and ongoing optimization 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 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 a portfolio of sub-brands, balancing sub-brand visual identities with core design system architectures.

• Focus on landing page layouts, micro-interactions, persuasive copywriting placement, and checkout/signup funnel optimization 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 for high-fidelity execution.

• Advocate for data-informed, evidence-based design decisions, presenting design concepts and experimentation rationale clearly to clients and stakeholders.

• Actively contribute to and maintain conversion-oriented design libraries, templates, and documented best practices to scale optimization efforts.

📝 Enhancement Note: The responsibilities highlight a deep dive into CRO-specific design tasks, including conversion-centered design, persuasive patterns, and funnel optimization. The requirement to work with "tokenized design systems" and "multi-brand navigation" indicates a need for sophisticated design system management and the ability to adapt designs across diverse brand identities while maintaining systemic consistency. The emphasis on collaboration within a "fast-paced, agile squad environment" points to a need for strong teamwork and communication skills.

🎓 Skills & Qualifications

Education: While not explicitly stated, a Bachelor's degree in Design, Human-Computer Interaction, Psychology, or a related field is typically expected for senior-level design roles, or equivalent practical experience.

Experience: 5-10 years of professional experience in UX/UI Design or Product Design, with a significant focus on conversion-centered design principles and digital product optimization.

Required Skills:

• Deep understanding and practical application 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.

• Proven ability to design distinct and unique user journeys for various sub-brands, balancing brand customization with core systemic rules.

• Strong understanding of front-end capabilities (HTML, CSS, and basic JavaScript limitations) to ensure optimization designs are technically feasible and performant.

• Strong understanding of web accessibility (WCAG) and page performance considerations.

• Comfortable presenting design rationale to stakeholders and working in fast-paced agile development/testing cycles.

• Experience designing high-converting experiences for e-commerce, transactional websites, lead-generation pages, or digital products. Preferred Skills:

• Experience designing for A/B testing, personalization, CRO, or landing page optimization, particularly where design decisions were 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.

📝 Enhancement Note: The "must-have portfolio" requirement is critical, emphasizing the need to showcase a clear end-to-end design process with specific examples of how user insights, data, or test hypotheses were used to design landing pages, optimized user flows, and successful A/B test variations. The preference for experience with CRO and A/B testing directly aligns with the role's core focus.

📊 Process & Systems Portfolio Requirements

Portfolio Essentials:

• Demonstrate a clear, end-to-end design process, highlighting how user insights, performance data, or test hypotheses informed design decisions.

• Showcase specific examples of designing landing pages, optimized user flows, and successful A/B test variations with measurable outcomes.

• Include case studies detailing the creation and application of design systems, particularly tokenized systems, for multi-brand environments.

• Present projects that illustrate a deep understanding of conversion-centered design principles and their impact on user engagement and business goals. Process Documentation:

• Clearly articulate the methodology used for user research, data analysis, and hypothesis generation in the context of CRO.

• Detail the workflow for designing, prototyping, and iterating on A/B test variations.

• Explain how technical feasibility and accessibility standards (WCAG) were integrated into the design process for experiments.

• Provide examples of collaboration with developers and stakeholders throughout the design and implementation lifecycle of optimization initiatives.

📝 Enhancement Note: The portfolio requirements are heavily skewed towards demonstrating practical application of CRO principles and data-informed design. The emphasis on tokenized design systems and multi-brand navigation suggests that the portfolio should also highlight the ability to manage complex design system implementations.

💵 Compensation & Benefits

Salary Range: Based on the Senior UX/UI Designer (CRO) title, 5-10 years of experience, and London location, a competitive salary range can be estimated. For London, UK, the average salary for a Senior UX/UI Designer typically falls between £55,000 and £80,000 per year. Given the specialized CRO focus and the agency environment (VML), the upper end of this range or slightly above might be achievable for a highly qualified candidate.

Benefits:

• Discretionary bonus scheme

• Training opportunities

• Competitive pension plan

• Medical insurance

• Life assurance

• Social events

• Opportunities to buy and sell holidays

• Family friendly policies

• Discounts with hundreds of retailers

Working Hours: Approximately 40 hours per week, with a hybrid work arrangement requiring an average of four days per week in the London office.

📝 Enhancement Note: The salary estimate is based on market research for Senior UX/UI Designers in London, UK, using data from reputable salary aggregators and industry benchmarks. The CRO specialization and agency context are factored in as potential drivers for compensation at the higher end of the typical range. The provided benefits are comprehensive and align with standard offerings for full-time employees in the UK creative/tech industry.

🎯 Team & Company Context

🏢 Company Culture

Industry: Marketing & Advertising / Creative Services / Digital Transformation. VML operates as a global creative company that integrates brand experience, customer experience, and commerce, positioning itself at the forefront of digital innovation for brands.

Company Size: VML is part of WPP, a very large global network. VML itself has principal offices in 55+ markets, indicating a substantial global presence and employee base. This means access to extensive resources and a wide array of client opportunities, but also a structured corporate environment.

Founded: VML was founded in 1992, with its current form as VML emerging from the merger of Wunderman Thompson and VML in 2024. This history signifies deep experience in marketing, advertising, and digital transformation, with a legacy of innovation and client service.

Team Structure:

• The role is embedded within a dedicated CRO squad, suggesting a cross-functional team structure comprising UX/UI Designers, CRO Strategists, Web Analysts, Product Managers, and front-end Developers.

• Reporting likely occurs within this squad structure, with potential for a design lead or Head of Design overseeing multiple squads.

• Cross-functional collaboration is paramount, with frequent interaction expected between design, analytics, strategy, and development teams to drive experimentation and optimization. Methodology:

• Data analysis and insights are central, with a strong emphasis on using user behavior analytics and A/B testing results to inform design decisions.

• Workflow planning and optimization strategies are executed through agile methodologies, focusing on iterative design and rapid testing cycles.

• Automation and efficiency practices are supported by the use of design systems, particularly tokenized systems, to ensure scalability and consistency across multiple brands and platforms.

Company Website: www.vml.com

📝 Enhancement Note: The company culture is shaped by its "Human First" philosophy, emphasizing empathy, trust, and genuine connections. The core values of Heart, Brains, and Courage suggest an environment that encourages both collaborative intelligence and bold, experimental solutions. The hybrid work model (4 days in office) indicates a belief in the value of in-person collaboration for creativity and team cohesion.

📈 Career & Growth Analysis

Operations Career Level: This role is at a Senior level within the UX/UI design discipline, with a specific specialization in Conversion Rate Optimization (CRO). It signifies a significant level of autonomy, expertise, and the ability to lead design initiatives within a specialized team. The focus is on driving measurable business outcomes through design.

Reporting Structure: The Senior UX/UI Designer (CRO) will likely report to a Design Lead, Head of Design, or potentially a CRO Lead within the dedicated CRO squad. They will work closely with peers in analytics, strategy, and development.

Operations Impact: The impact of this role is directly tied to revenue growth and business performance through conversion rate optimization. By designing and testing improvements to user journeys, landing pages, and digital products, this role directly influences key business metrics such as conversion rates, customer acquisition costs, and customer lifetime value.

Growth Opportunities:

• Specialization Deepening: Opportunity to become a leading expert in CRO design, potentially mentoring junior designers and influencing best practices across the organization.

• Skill Expansion: Potential to expand into broader product design leadership, strategic UX planning, or even client-facing strategy roles within the agency.

• Leadership Development: With proven success, opportunities may arise to lead design initiatives, manage project streams, or even take on team leadership responsibilities within the CRO squad or broader design department.

📝 Enhancement Note: The growth path for this role is clearly defined by deepening specialization in CRO and UX, or by moving into broader design leadership. The agency context offers exposure to diverse brands and challenges, providing a rich environment for skill development and career progression.

🌐 Work Environment

Office Type: Hybrid work model, with an expectation of being in the London office an average of four days per week. This suggests a modern, collaborative office space designed to facilitate teamwork, brainstorming, and client interactions.

Office Location(s): London, England, United Kingdom. Specific office address details would typically be provided during the interview process.

Workspace Context:

• The environment is designed for collaboration, with the CRO squad working closely together. This implies open-plan areas, meeting rooms equipped for brainstorming, and potentially dedicated project spaces.

• Access to the latest design tools (Figma is mentioned prominently) and potentially analytics platforms will be standard.

• Opportunities for frequent interaction with a diverse range of professionals—CRO strategists, analysts, product managers, developers, and potentially client teams—are inherent to the role.

Work Schedule: Standard full-time working hours (estimated 40 hours/week) with a hybrid arrangement. Flexibility may be available, but the expectation of 4 days in-office suggests a structured approach to in-person collaboration.

📝 Enhancement Note: The hybrid model with a specified number of office days indicates a deliberate strategy to balance remote flexibility with the benefits of in-person collaboration, crucial for a design and CRO-focused team.

📄 Application & Portfolio Review Process

Interview Process:

• Initial Screening: Likely a brief call with an HR or recruitment representative to assess basic qualifications, experience, and cultural fit.

• Portfolio Review & Design Challenge: A key stage will involve presenting your portfolio, discussing your process, and potentially undertaking a design challenge focused on CRO principles, landing page optimization, or a similar problem. This will assess your practical skills and strategic thinking.

• Squad/Team Interview: Meeting with members of the CRO squad (e.g., CRO Strategist, Analyst, Developer) to evaluate collaboration style, technical understanding, and ability to work within an agile team.

• Hiring Manager Interview: A final discussion with the Design Lead or Hiring Manager to assess overall fit, career aspirations, and strategic alignment.

Portfolio Review Tips:

• Highlight CRO Impact: For each project, clearly articulate the problem, your role, the process, the specific design solutions, and – most importantly – the measurable results (e.g., conversion rate lift, engagement increase). Use data and A/B test results where possible.

• Showcase Process: Detail your approach to user research, hypothesis generation, wireframing, prototyping, and UI design, particularly as it relates to experimentation.

• Design System Expertise: Include examples demonstrating your proficiency with design systems, especially tokenized systems, and how you've managed multi-brand applications.

• Figma Proficiency: Be prepared to discuss your Figma workflow, component structure, and prototyping capabilities.

• Storytelling: Frame your projects as compelling narratives that showcase your problem-solving skills and ability to drive business outcomes.

Challenge Preparation:

• Familiarize yourself with common CRO heuristics and best practices for landing pages, forms, and checkout funnels.

• Be prepared to analyze a given scenario or website, identify optimization opportunities, and propose design solutions supported by rationale.

• Practice articulating your design decisions clearly, linking them to user needs and business objectives.

• Understand the technical constraints and opportunities relevant to web development (HTML, CSS, JS).

📝 Enhancement Note: The interview process will heavily scrutinize the candidate's ability to translate design skills into measurable CRO outcomes. The portfolio is the primary tool for demonstrating this, and candidates should prepare to deep-dive into specific projects.

🛠 Tools & Technology Stack

Primary Tools:

• Figma: Essential for UI design, prototyping, and design system management. Expect advanced usage, including component libraries and design tokens.

• Prototyping Tools: Beyond Figma, potentially InVision, Axure, or similar for more complex interaction models.

• Design Systems: Experience with building, maintaining, and leveraging tokenized design systems is critical.

Analytics & Reporting:

• Web Analytics Platforms: Familiarity with tools like Google Analytics, Adobe Analytics, or similar is crucial for understanding user behavior and testing results.

• A/B Testing Tools: Experience with platforms such as Optimizely, VWO (Visual Website Optimizer), Adobe Target, or Google Optimize.

• Data Visualization Tools: Basic understanding of how data is presented and interpreted, potentially using tools like Tableau, Power BI, or Looker Studio.

CRM & Automation:

• While not a direct CRM role, understanding how CRM data might inform user segmentation or personalization efforts could be beneficial.

• Familiarity with marketing automation platforms might be a plus for understanding the broader customer journey context.

📝 Enhancement Note: Proficiency in Figma and a strong understanding of A/B testing platforms are non-negotiable. The role requires an ability to interpret data from analytics and testing tools to inform design decisions.

👥 Team Culture & Values

Operations Values:

• Heart: Empathy and trust are key, fostering genuine connections and human-centric work. This translates to understanding user needs deeply and collaborating respectfully with team members.

• Brains: Relentless curiosity and collaborative intelligence are valued for solving complex challenges. This means a proactive approach to learning, data analysis, and problem-solving.

• Courage: Encouraging individuals to speak up, embrace experimentation, and advocate for bold solutions. This implies a willingness to challenge the status quo and propose innovative, data-backed design ideas.

• Data-Driven: A strong emphasis on evidence-based design decisions, using performance data and test learnings as the foundation for optimization strategies.

• Efficiency & Scalability: Working with design systems and optimizing processes to ensure consistency and effectiveness across multiple brands and projects.

Collaboration Style:

• Cross-functional Integration: Working seamlessly within the CRO squad, involving designers, strategists, analysts, and developers in a cohesive unit.

• Process Review & Feedback: A culture that encourages open feedback loops on designs, test hypotheses, and optimization strategies to continuously improve outcomes.

• Knowledge Sharing: Actively contributing to design libraries, templates, and best practices to empower the wider team and scale optimization efforts effectively.

📝 Enhancement Note: The company's core values (Heart, Brains, Courage) are directly applicable to a CRO and UX role, emphasizing user empathy, analytical rigor, and the bravery to test innovative solutions.

⚡ Challenges & Growth Opportunities

Challenges:

• Balancing Brand Identity with Systemic Rules: Designing for multiple sub-brands within a unified design system requires careful navigation of unique brand requirements versus core system components and guidelines.

• Translating Data into Actionable Design: Effectively interpreting complex user data, A/B test results, and analytics to generate concrete, impactful design variations that drive measurable improvements.

• Agile Pace & Multi-Project Management: Thriving in a fast-paced, agile environment where managing multiple experimentation pipelines and delivering high-quality designs under tight deadlines is essential.

• Technical Feasibility Constraints: Ensuring that innovative design concepts are technically feasible for front-end implementation and performant across various devices and browsers.

Learning & Development Opportunities:

• CRO Specialization: Deepen expertise in conversion rate optimization methodologies, user psychology, and advanced experimentation techniques.

• Design System Mastery: Further develop skills in building, managing, and scaling sophisticated tokenized design systems for complex multi-brand ecosystems.

• Cross-Functional Acumen: Gain deeper insights into web analytics, CRO strategy, and product management through close collaboration with specialized teams.

• Client Exposure: Work with a diverse portfolio of brands, potentially leading to opportunities in client strategy and relationship management within the agency.

📝 Enhancement Note: The challenges are inherent to the specialized nature of CRO and working within a large agency environment. The growth opportunities are geared towards becoming a leader in CRO design and leveraging this expertise for broader career advancement.

💡 Interview Preparation

Strategy Questions:

• "Describe a time you used user data or A/B test results to significantly improve a conversion rate. What was your process, and what were the outcomes?" (Prepare a detailed case study focusing on data-driven design decisions and measurable impact.)

• "How do you approach designing for multiple sub-brands within a single design system? Walk us through an example of balancing brand-specific needs with systemic consistency." (Focus on your understanding of tokenized design systems and multi-brand strategy.)

• "Imagine we have a high bounce rate on a key landing page. What steps would you take, from a UX/UI perspective, to diagnose the problem and propose design solutions for A/B testing?" (Demonstrate your diagnostic process, hypothesis generation, and iterative design approach.) Company & Culture Questions:

• "What excites you about VML's 'Human First' philosophy and its core values of Heart, Brains, and Courage?" (Connect these values to your personal work style and approach to design and collaboration.)

• "How do you see your role contributing to a dedicated CRO squad and the broader agency goals?" (Emphasize your collaborative spirit and focus on driving business impact.)

• "How do you stay current with trends in UX/UI design, CRO, and digital product development?" (Showcase your commitment to continuous learning.) Portfolio Presentation Strategy:

• Prioritize CRO Impact: Select 3-4 projects that best showcase your CRO and A/B testing experience. For each, clearly define the business problem, your specific contributions, the design solutions, and the quantifiable results.

• Detail Your Process: For each project, walk through your methodology: research, ideation, wireframing, prototyping, UI design, and how you incorporated data and user feedback.

• Highlight Design Systems: If applicable, dedicate time to explaining your experience with design systems, particularly tokenized systems, and how you've managed them across different brands or platforms.

• Be Ready for Technical Questions: Prepare to discuss the technical feasibility of your designs and your understanding of front-end constraints (HTML, CSS, JS).

• Engage and Discuss: Treat the portfolio review as a conversation. Be prepared to answer questions about your decisions, challenges, and learnings.

📝 Enhancement Note: Interview preparation should heavily focus on quantifiable results and a clear demonstration of the candidate's ability to connect design work directly to business objectives, particularly conversion rates.

📌 Application Steps

To apply for this Senior UX/UI Designer (CRO) position:

• Submit your application through the VML careers portal via the provided link.

• Curate Your Portfolio: Select 3-4 of your strongest projects that specifically highlight your experience in Conversion Rate Optimization (CRO), A/B testing, and designing for high-converting user journeys. Ensure each case study clearly outlines the problem, your process, the design solution, and measurable results.

• Optimize Your Resume: Tailor your resume to emphasize your expertise in UX/UI design, CRO principles, Figma proficiency, design systems, and experience with A/B testing platforms. Quantify achievements wherever possible.

• Prepare Your Presentation: Practice walking through your portfolio projects concisely, focusing on the impact of your design decisions on conversion rates and business goals. Be ready to articulate your thought process and answer in-depth questions about your work.

• Research VML and its Values: Understand VML's "Human First" philosophy and its core values (Heart, Brains, Courage). Consider how your own approach aligns with these principles and how you can contribute to their culture.

⚠️ Important Notice: This enhanced job description includes AI-generated insights and operations industry-standard assumptions. All details should be verified directly with the hiring organization before making application decisions.