twentyAI are partnering with a leading European health, fitness, and leisure group in their search for a Senior Data Scientist. With a large portfolio of premium wellness clubs across the UK and mainland Europe, this organisation is transforming how people experience fitness and wellbeing—through innovative services, exceptional member experiences, and a vibrant community-first approach.

They are currently looking for a Senior Data Scientist to lead machine learning initiatives focused on pricing strategy and consumer behavior insights. This role offers the chance to combine hands-on data science with technical leadership and mentorship responsibilities, in a business where data is core to decision-making.

The Opportunity

This Senior Data Scientist will play a critical role in shaping the company’s approach to personalized wellness, pricing models, and member engagement strategies. It’s a chance to lead meaningful projects from end to end—while also mentoring and developing the internal data team.

They’re looking for a commercially minded data expert who’s excited by the idea of turning complex behavior patterns into actionable insights, and who’s equally comfortable leading initiatives as they are rolling up their sleeves in the code.

Key Responsibilities

• Lead development of machine learning models focused on dynamic pricing, membership lifecycle value, and consumer segmentation.
• Mentor and support other members of the data science team.
• Collaborate with stakeholders across marketing, product, and operations to deliver insights and build scalable, data-driven solutions.
• Present findings to senior leadership, influencing strategy with robust, explainable data models.
• Foster a culture of experimentation and continuous improvement within the data function.

About You

• 5-7 years of experience in a data science role, with proven success leading projects and mentoring others.
• Advanced proficiency in Python (or R) and SQL.
• Strong experience with machine learning frameworks and tools such as scikit-learn, XGBoost, TensorFlow, or similar.
• A solid understanding of statistical modeling and behavioral analytics.
• Comfortable translating technical insights into strategic business recommendations.
• Previous experience in subscription-based, consumer-facing, or wellness/lifestyle industries would be highly beneficial.

Please note the company is based in Hatfield and is operating a hybrid policy of min 2 days per week in office.