---
title: 'Lead Data Scientist at Referrals Only'
canonical: 'https://feeny.ai/job/lead-data-scientist-referrals-only-cardiff-london-or-5f4sv8dv8nvh'
type: 'job'
last_seen: '2026-09-14'
---

# Lead Data Scientist at Referrals Only

- **Company:** Referrals Only
- **Location:** Cardiff London OR, United Kingdom
- **Work type:** remote
- **Posted:** 2026-04-28
- **Last confirmed live:** 2026-09-14
- **Apply:** https://job-boards.greenhouse.io/monzoreferrals/jobs/7861417

## Job description

📍London or Barcelona | UK remote | 💰 £95,000 to £130,000 + Incentive Awards tied to your performance +[Benefits](https://monzo.com/careers/#benefits)|[Technology](https://monzo.com/blog/technology) -[Data](https://monzo.com/blog/data)

About our Data Science Teams:

We're looking for a Lead Data Scientist excited to help build the bank of the future. You'll have the opportunity to super charge our user engagement in 2026 and help us to build a bank that customers truly love.

At Monzo, we're building a bank that is fair, transparent and a delight to use. We’re growing extremely fast and have over 11 million customers in the UK. We’ve built a product that people love and more than 80% of our growth comes from word of mouth and referrals.

Enable Monzo to Make Better Decisions, Faster

We have a strong culture of data-driven decision making across the whole company. And we're great believers in powerful, real-time analytics and empowerment of the wider business. All our data lives in one place and is super easy to use. 90% of day-to-day data-driven decisions are covered by self-serve analytics through Looker which gives data scientists the head space to focus on more impactful business questions and analyses.

## How we hire

We are excited to be expanding and are hiring for multiple roles across our Data Science teams! Whether your interests lie in Borrowing, Growth, Payments, Fincrime, Wealth, or Core, we are looking for talented individuals with a versatile skill set to contribute across our squads. While we allocate teams after the interview process, we aim to match your skills and aspirations with the most suitable role. Throughout the process, you will meet team members from across our Data Science collectives, who will guide you through the opportunities available. Join us and be part of shaping our future!

What you’ll be working on:

- Lead the data strategy and continue to evolve Monzo for our customers to make it magically simple to manage money day-to-day
- Develop and execute best practices for experimentation enabling our team to make data informed decisions
- Collaboratively set standards and work with data across Monzo, fostering knowledge sharing and continuously improving data practices.
- Work closely with leaders in product, engineering, design and research to build and iterate on product ideas

You should apply if:

- You enjoy working with cross functional fast moving teams
- You are able to think strategically about commercial products and how decisions using data can unlock more value for our customers
- You are excited about mentoring other data scientists and analytics engineers
- You are excited by experimentation and utilising new data techniques to solve challenging problems
- You want to understand the nuances of our data and are excited about laying the key foundational knowledge for our new products and features
- You are opinionated about how to think about measuring success and are willing to challenge the status quo

The interview process:

Our interview process involves:

- Recruiter Call
- Initial Call
- Technical assessment
- Final Interviews
- Business Fit/Collaboration
- Case Study
- Technical Interview

Our average process takes around 2-3 weeks but we will always work around your availability. You will have the chance to speak to our recruitment team at various points during your process.

One of our recruiters has written a blog on the process, for extra details, hints and tips please see[Data Hiring at Monzo](https://monzo.com/blog/2022/03/21/data-hiring-at-monzo)

What’s in it for you:

💰 £95,000 to £130,000 + Incentive Awards tied to your performance + Benefits

✈️ We can help you relocate to the UK or Spain

✅ We can sponsor visas

📍This role can be based in our London or Barcelona offices, but we're also open to distributed working within the UK (with ad hoc meetings in London).

⏰ We offer flexible working hours and trust you to work enough hours to do your job well, at times that suit you and your team.

📚Learning budget of £1,000 a year for books, training courses and conferences

➕And much more, see our full list of benefits [here](https://monzo.com/careers/)

If you prefer to work part-time, we'll make this happen whenever we can - whether this is to help you meet other commitments or strike a great work-life balance.

#LI-NB2 #LI-Remote

## About Referrals Only

## Company Overview
- **One-liner**: Marqeta is the world’s first modern card issuing platform, providing open APIs that enable businesses to create, manage, and scale customized payment card programs.
- **Entity Type**: Public (Ticker: MQ on NASDAQ)
- **Headquarters**: Oakland, California, USA
- **Founded**: 2010
- **Founders**: Jason Gardner (Founder & Executive Chairman)

## Core Business
- **Primary industry**: Financial Technology (Fintech) — Modern Card Issuing & Payment Solutions
- **Target customers**: B2B; serves a wide range of industries including digital banking, on-demand delivery, buy now, pay later, expense management, retail, and workforce payments. Customers include Square, DoorDash, and other high-growth fintech and enterprise companies.
- **Mission or purpose statement**: To simplify payments and enable any company to deliver delightful payment experiences natively, powering more flexible, engaging, and innovative payment products.

## Products & Services
- **Modern Card Issuing Platform (SaaS/API)**: Fully open API platform that allows developers to launch new credit and debit card programs with speed, flexibility, and scale. Supports instant wage access, embedded finance, and custom card products.
- **Compliance & Risk Management (Service)**: Integrated fraud detection, spend control, and compliance tools to ensure high levels of security and uptime.
- **Global Expansion Capabilities (Platform)**: Certified to operate in over 40 countries across the US, Europe, and Asia, enabling businesses to scale globally.

## Market Standing
- **Valuation/Market Cap**: As a public company, market cap fluctuates. As of mid-2026, Marqeta is a publicly traded company valued in the multi-billion dollar range (exact figure varies with market conditions).
- **Key Metric**: Annual Revenue — $383 billion+ in total volume processed in 2025; 80x volume growth since 2017; 99.99% platform uptime in 2025.
- **Notable Investors/Partners**: Key customers include Square (Block), DoorDash, and other leading fintech and enterprise firms. Partners include issuing banks, networks (e.g., Visa, Mastercard), and card fulfillment providers.
- **Growth Signals**: Recognized as a CNBC Disruptor (top 50 in 2021 award); consistent expansion into new geographies (EU, UK, Asia); continued hiring across multiple departments and regions (US, Canada, UK).

## Competitive Advantages
- **First-mover & category leader**: Marqeta defined the modern card issuing category with its open API platform, giving it a decade-plus head start over competitors.
- **Scalability & reliability**: Proven track record of 99.99% uptime and handling massive transaction volumes (80x growth since 2017) — critical for enterprise customers.
- **Deep integration with major networks**: Pre-existing relationships with Visa, Mastercard, and issuing banks shorten time-to-market for customers.
- **Developer-first approach**: Open APIs and developer tools make it easy for engineering teams to build custom payment experiences quickly.

## Strategic Focus
- **Global expansion**: Continuing to expand its certified operations into new countries (currently 40+) to serve multinational customers.
- **Embedded finance & new use cases**: Driving adoption in instant wage access, embedded finance, and enterprise expense management.
- **AI & automation**: Investing in AI-powered fraud detection, risk management, and product automation (e.g., hiring for Principal Security Engineer, Product & AI; Lead Product Manager, Enterprise AI & Automation).
- **Platform stability & security**: Maintaining industry-leading uptime and security compliance as core differentiators.

## Why Work Here
- **Culture & values**: Marqeta emphasizes a culture of “Simplify and Innovate,” “Solve for the Customer,” “Do What’s Right,” “Make it Count,” and “Win as a Team.” Employee Resource Groups (ERGs) include BlackCard, HOLA, RepresentAsian, Desi, MQ-Proud, Vets@MQ, Women’s Group, Parents’ Group, and Marqetaglots.
- **Remote/hybrid policy**: Many roles are remote (US, Canada, UK), with some positions based in Oakland, CA or London, UK. The company supports flexible work arrangements.
- **Notable perks & engineering culture**: Fast-paced, purpose-driven environment; strong focus on developer experience and open APIs; opportunities to work on cutting-edge payment infrastructure at massive scale. The company invests heavily in early career talent and internal mobility.
- **Award-winning workplace**: Recognized as a top workplace (e.g., CNBC Disruptor) and offers a collaborative, inclusive environment.

## Sources
1. [Marqeta About Us](https://www.marqeta.com/company/about-us)
2. [Marqeta Careers Page](https://www.marqeta.com/company/careers)
3. [Marqeta Homepage](https://www.marqeta.com/)
4. [Greenhouse Job Board](http://job-boards.greenhouse.io/marqeta)
5. [MQ Referrals Job Board](https://job-boards.greenhouse.io/mqreferrals/jobs/7743043)

## Other roles at Referrals Only

- [Data Science Manager](https://feeny.ai/job/data-science-manager-referrals-only-cardiff-london-or-qy9svbyf8q50) — Cardiff London OR, United Kingdom
- [Product Manager, Subscriptions](https://feeny.ai/job/product-manager-subscriptions-referrals-only-barcelona-0jkx6zdsjnj7) — Barcelona, Spain
- [Fraud Compliance Manager](https://feeny.ai/job/fraud-compliance-manager-referrals-only-united-kingdom-qpzb7bmcbgxt) — United Kingdom
- [Fraud Investigator, Overnight Team](https://feeny.ai/job/fraud-investigator-overnight-team-referrals-only-united-kingdom-weayv59k72r1) — United Kingdom
- [Lead Market Researcher](https://feeny.ai/job/lead-market-researcher-referrals-only-cardiff-london-or-83qyn2ncq2qk) — Cardiff London OR, United Kingdom
- [Chief of Staff, Group CFO](https://feeny.ai/job/chief-of-staff-group-cfo-referrals-only-london-fg8xem42f7fh) — London, United Kingdom
- [Senior Product Manager - Growth](https://feeny.ai/job/senior-product-manager-growth-referrals-only-london-x8w3pax4qj7r) — London, United Kingdom
- [Director of Product Design](https://feeny.ai/job/director-of-product-design-referrals-only-cardiff-london-or-8ca0hy3vyc09) — Cardiff London OR, United Kingdom
- [Staff Backend Engineer](https://feeny.ai/job/staff-backend-engineer-referrals-only-cardiff-london-or-6w1n8z0gktm9) — Cardiff London OR, United Kingdom
- [Senior Backend Engineer](https://feeny.ai/job/senior-backend-engineer-referrals-only-cardiff-london-or-0weyav3xnjw9) — Cardiff London OR, United Kingdom