Senior Data Scientist

We are looking for a Senior Data Scientist to lead the design and delivery of machine learning, statistical modelling and experimentation solutions that solve complex business problems and drive measurable outcomes across our client base. You will combine hands-on technical expertise with strong consulting and stakeholder skills, shaping analytical approaches, guiding delivery and translating data into clear, actionable insight.

The role focuses on developing scalable data science solutions, validating performance through robust experimentation, leading technical decision-making and partnering with senior stakeholders to ensure analytical outputs deliver real commercial impact.

About us

Optima Partners is a fast-growing professional services firm helping leading organisations transform customer engagement at the intersection of marketing, technology and data. We work with major brands including Lloyds Banking Group, NatWest, Nationwide, Aviva, Virgin Media O2, BT, Centrica, and GSK. As we scale from 80 to 200 people we’re growing our Advanced Data team.

We are collaborative, curious and focused on delivering practical insight that helps organisations make better decisions and grow sustainably. You will join a practitioner-led business with a strong data science community, working alongside people who are passionate about applying analytical thinking to real-world business problems.

About the role

As a Senior Data Scientist, you will be a technical lead responsible for shaping, developing and implementing machine learning and statistical solutions that deliver meaningful value for our clients. You will work closely with senior stakeholders to understand business challenges, define analytical strategies, oversee delivery and turn complex outputs into clear, actionable recommendations.

This is a great opportunity for an experienced data scientist to take ownership of high-impact work across multiple commercial sectors, contribute to multi-disciplinary project teams and play a visible role in growing and developing our data science practice.

What you will be doing

· Leading the development and implementation of machine learning and statistical models to solve practical, high-value business problems

· Partnering with senior stakeholders to understand objectives, shape analytical approaches, influence decisions and communicate findings effectively

· Translating complex technical outputs into clear, transparent and actionable recommendations that support strategic decision-making

· Exploring data, testing hypotheses and identifying opportunities to create customer, operational and commercial value

· Collaborating with and guiding teams across data science, engineering, strategy and design to deliver high-quality outcomes

· Championing emerging data science techniques, including practical applications of Large Language Models, and helping translate them into client-ready solutions

· Mentoring junior colleagues, reviewing analytical work and contributing to the development of best practice within the Advanced Data team

What we would like you to have

· Strong academic background in mathematics, statistics, science, engineering or another numerate discipline

· Minimum 2:1 degree in a STEM subject, with a postgraduate qualification in a quantitative field considered beneficial

· Deep knowledge of statistics, including experimental design, uncertainty quantification, causal inference and predictive modelling

· Significant experience applying supervised and unsupervised machine learning techniques in commercial or client-facing environments

· Advanced proficiency in Python and/or R, with experience operationalising data science solutions and working with modern data science tooling

· Excellent communication skills, with the ability to explain complex analysis clearly and confidently to technical and non-technical audiences

· Strong problem-solving skills, commercial curiosity and the ability to lead work independently while supporting others in small, high-performing teams

· Strong understanding of commercial value drivers such as revenue, cost, profitability, customer behaviour and operational performance

· Experience mentoring junior data scientists, reviewing analytical approaches and contributing to technical standards or reusable assets

Why join us

At Optima, you will work on varied, meaningful projects for well-known organisations while continuing to deepen your technical expertise and leadership capability. You will be part of a supportive data science community with a strong culture of continuous learning, knowledge sharing and collaboration.

You will have the opportunity to shape analytical solutions across different sectors, learn from experienced practitioners, mentor others and build a career path with clear opportunities for senior development and progression.

What’s on offer

• Competitive salary + bonus up to 15%

• 37 days holiday (incl. Christmas shutdown)

• Private medical insurance, life & income protection

• Pension scheme

• 1,000+ employee perks

• Dedicated learning, training, and certification support

If you’re ready to take a senior role in a practitioner-led consultancy where data science is applied to meaningful, real-world problems, we’d love to hear from you.