Senior Data Analyst - Fraud Prevention Location: London

Location: London

Employment Type: Full time

Location Type: Hybrid

Department: Data

What you’ll be doing:

• Work with outputs from ML models to maintain and improve fraud prevention decision, balancing detection coverage against false positive rates.
• Own the fraud rule lifecycle - designing, testing, and maintaining prevention rules, with a clear view of coverage, false positive trade-offs, and when to retire what's no longer working.
• Partner with Fraud Operations to understand emerging abuse patterns and translate operational observations into analytical improvements.
• Design and maintain alerting systems that identify threats early, giving the team time to respond before incidents escalate.
• Forecast fraud losses and chargeback volumes, giving Finance and Risk leadership earlier visibility into projected exposure.
• Define and own the north star metrics and KPIs for fraud prevention, ensuring reporting is clear, owned, and actionable at the executive level.
• Act as the data bridge between Product and the Applied AI team – providing performance feedback that informs model updates and roadmap prioritisation.
• Support the evaluation of third-party fraud prevention providers, bringing data-driven criteria to vendor assessments.
• Collaborate with Data and Analytics Engineering to ensure fraud-related data is tracked, governed, and handled in line with PII requirements.

What you need to succeed:

• 4+ years of experience in fraud analytics, risk analysis, or a closely related payments/trust & safety domain.
• Strong SQL and Python proficiency – comfortable writing analytical queries across large transactional datasets, building monitoring logic, and applying statistical techniques to fraud and risk problems.
• Experience designing and maintaining dashboards or alerting systems with clear signal-to-noise discipline.
• Strong analytical communication – able to turn ambiguous fraud signals into crisp, actionable narratives for operational and executive audiences.
• Experience collaborating with cross-functional teams including Operations, Engineering, and Product.
• Ability to leverage AI tools and agents as a force multiplier for analysis, while maintaining the critical thinking to interrogate outputs, spot gaps, and own the conclusions.
• Experience mentoring junior and mid-level analysts, helping them grow their technical skills, develop analytical judgement, and raise the quality of the team's output.

Nice to have:

• Prior experience working in a marketplace or two-sided platform.
• Experience with payment processing concepts – chargebacks, dispute flows, authorisation rates, PSP dynamics.
• Exposure to compliance or regulatory frameworks (PSD2/3, AML, KYC).

Why you’ll love it at Preply:

• An open, collaborative, dynamic and diverse culture.
• A generous monthly allowance for lessons on Preply.com, Learning & Development budget and time off for your self-development.
• A competitive financial package with equity, leave allowance and health insurance.
• Not in Barcelona? We offer an attractive relocation package to join us in our Preply Barcelona Hub.
• Access to free mental health support platforms.
• Access to Gympass-partnered wellness and gym centres throughout Spain to promote and support well-being and physical health.
• The opportunity to unlock the potential of learners and tutors through language learning and teaching in 175 countries (and counting).

Diversity, Equity, and Inclusion:

Preply.com is committed to creating an inclusive environment where people of diverse backgrounds can thrive. We believe that the presence of different opinions and viewpoints is a key ingredient for our success as a multicultural Ed-Tech company. That means that Preply will consider all applications for employment without regard to race, color, religion, gender identity or expression, sexual orientation, national origin, disability, age or veteran status.