1. What is a Data Scientist at Brex?

As a Data Scientist at Brex, you are stepping into a pivotal role at the forefront of the AI-powered spend platform. Brex helps tens of thousands of companies—from fast-growing startups to global enterprises like DoorDash and Flexport—spend with confidence. The Data team here does not just build dashboards; we turn information into a strategic advantage. You will treat data as a product, and your ownership of that product will run deep.

In this role, you are embedded directly within cross-functional units such as Product, Engineering, Risk, Operations, and Customer Success. Your primary objective is to understand the complex interactions between product engagement, customer retention, and overall growth. Whether you are optimizing user workflows for our travel and expense software or uncovering insights that increase long-term customer value, your work will directly shape high-impact strategic decisions.

Working at Brex allows you to push your limits and challenge the status quo. If you are excited by complexity and want your analytical work to drive sustainable revenue growth and operational efficiency at a massive scale, this is exactly where you belong. Expect a fast-paced environment where your product intuition is valued just as highly as your technical rigor.

2. Common Interview Questions

The following questions are representative of what candidates face during the Brex interview process. They are designed to illustrate patterns in how we evaluate analytical thinking, not to serve as a memorization checklist.

Product Sense & Metrics

This category tests your ability to define success and troubleshoot product performance using data.

• How would you measure the success of a newly launched feature that automatically categorizes corporate card expenses?
• If the overall transaction volume on the Brex platform goes up, but revenue stays flat, what data would you look at to understand why?
• How would you design a metric to capture the "health" of our customer support ecosystem?
• We want to launch a new rewards program for early-stage startups. How would you determine if it is cannibalizing our existing revenue streams?
• Walk me through how you would segment our user base to find opportunities for upselling our travel software.

Applied Statistics & Experimentation

This category assesses your rigor in designing tests and validating hypotheses.

• Design an A/B test for a new checkout flow. How do you determine the required sample size?
• What would you do if an A/B test shows a statistically significant increase in user engagement, but a decrease in short-term revenue?
• Explain p-value and confidence intervals to a non-technical Product Manager.
• How do you account for multiple testing if we are evaluating 10 different metrics in a single experiment?
• If standard randomized A/B testing is not possible due to a small enterprise customer base, how would you measure the impact of a product change?

Data Manipulation & Coding

This category evaluates your hands-on ability to extract and clean data under time pressure.

• Write a SQL query to calculate the rolling 7-day average spend per customer segment.
• Given a table of user logins and a table of card transactions, write a query to find the percentage of users who make a transaction within 24 hours of logging in.
• In Python, how would you handle a dataset with 20% missing values in a critical financial column before building a model?
• Write a SQL query using window functions to identify the first time each company spent over $10,000 in a single month.

Behavioral & Leadership

This category checks your alignment with Brex's culture of ownership and collaboration.

• Tell me about a time when your data analysis contradicted the leadership team's intuition. How did you handle it?
• Describe a project where you had to define the problem from scratch because the initial request was too vague.
• How do you prioritize your time when you receive urgent requests from multiple stakeholders simultaneously?

3. Getting Ready for Your Interviews

Preparing for a Data Scientist interview at Brex requires a balanced approach. We do not just look for people who can write flawless code; we look for strategic thinkers who can translate ambiguous business problems into actionable data models.

Here are the key evaluation criteria you will be measured against:

Product Intuition & Business Acumen – You must demonstrate a deep understanding of how users interact with financial products. Interviewers will evaluate your ability to tie data metrics directly to customer retention, engagement, and revenue growth. You can show strength here by always framing your technical solutions within the context of the broader business impact.

Technical Rigor & Execution – This covers your proficiency in SQL, Python or R, and applied statistics. We evaluate your ability to manipulate complex datasets, design robust experiments, and build scalable data models. Strong candidates write clean, efficient code and can explain the statistical foundations behind their chosen methodologies.

Problem Solving & Ambiguity Navigation – At Brex, you will rarely be handed a perfectly scoped problem. Interviewers will assess how you break down open-ended questions, state your assumptions, and structure a logical path to a solution. You can excel here by proactively communicating your thought process and asking clarifying questions.

Ownership & Collaboration – Because our data scientists are embedded across various teams, your ability to communicate complex insights to non-technical stakeholders is critical. We look for candidates who take end-to-end ownership of their work and can influence product strategies through clear, compelling data storytelling.

4. Interview Process Overview

The interview process for a Data Scientist at Brex is designed to be rigorous, fair, and highly reflective of the actual day-to-day work. It typically begins with an initial recruiter screen to align on your background, career goals, and fundamental fit for the role. This is followed by a technical screen, which usually involves live coding in SQL and Python to assess your baseline data manipulation and analytical problem-solving skills.

If you advance, you will move to the core of the evaluation: a comprehensive onsite loop (conducted remotely). This loop consists of several distinct rounds focusing on product sense, applied statistics and experimentation, advanced technical execution, and behavioral alignment. Brex places a heavy emphasis on how you approach product analytics, meaning you will face scenario-based questions that mirror real challenges our Product and Engineering teams tackle daily.

What sets the Brex process apart is the focus on "data as a product." You will not just be asked to compute a p-value or write a window function; you will be asked why that metric matters to our customers and how it improves the Brex platform.

This visual timeline outlines the typical stages of your interview journey, from the initial recruiter screen through the final onsite rounds. Use this roadmap to structure your preparation, ensuring you allocate enough time to practice both your technical coding skills and your high-level product strategy frameworks. Keep in mind that specific rounds may vary slightly depending on whether you are interviewing for a Product Analytics or Finance-focused data science pod.

5. Deep Dive into Evaluation Areas

To succeed in the Brex interview process, you need to be exceptionally prepared across several core competencies. Below is a detailed breakdown of the primary evaluation areas.

Product Analytics & Metrics Design

Understanding the "why" behind user behavior is crucial. This area tests your ability to define success metrics, identify root causes for metric shifts, and propose product improvements based on data. Strong performance means you do not just list standard metrics; you tailor them specifically to Brex's B2B financial products.

Be ready to go over:

• Metric formulation – Defining primary, secondary, and guardrail metrics for a new feature launch.
• Root cause analysis – Investigating a sudden drop in corporate card usage or an increase in expense reporting drop-offs.
• User lifecycle analysis – Measuring activation, engagement, and churn in a SaaS or fintech context.
• Advanced concepts (less common) – Cannibalization effects, network effects in B2B payments, and sophisticated LTV/CAC modeling.

Example questions or scenarios:

• "If the activation rate for our new integrated travel booking software dropped by 15% week-over-week, how would you investigate the cause?"
• "How would you design a dashboard to monitor the health of our global payments product?"
• "What metrics would you use to evaluate whether a new automated receipt-matching feature is successful?"

Applied Statistics & Experimentation

Because Data Scientist roles at Brex heavily influence product strategy, you must be highly proficient in designing and evaluating A/B tests. Interviewers want to see that you understand the mathematical principles behind experimentation and can identify when standard A/B testing is not appropriate.

Be ready to go over:

• Experiment design – Choosing randomization units, determining sample sizes, and defining minimum detectable effects (MDE).
• Statistical concepts – P-values, confidence intervals, statistical power, and Type I/Type II errors.
• Handling practical challenges – Dealing with novelty effects, day-of-week seasonality, and non-normal distributions.
• Advanced concepts (less common) – Causal inference, synthetic control methods, and multi-armed bandits.

Example questions or scenarios:

• "Design an experiment to test a new onboarding flow for enterprise customers. What are the potential pitfalls?"
• "How would you analyze an A/B test where the sample size is extremely small due to targeting a niche segment of startup founders?"
• "Explain how you would handle interference or network effects if we tested a new referral program."

Technical Execution (SQL & Python/R)

You cannot treat data as a product if you cannot extract and manipulate it efficiently. This area evaluates your hands-on coding ability. Strong candidates write optimized, readable code and are comfortable navigating complex, messy datasets.

Be ready to go over:

• Advanced SQL – Complex joins, window functions, CTEs (Common Table Expressions), and aggregations.
• Data manipulation in Python/R – Using Pandas or Dplyr to clean, merge, and transform data.
• Edge cases – Handling null values, duplicates, and data anomalies gracefully.

Example questions or scenarios:

• "Write a SQL query to find the top 3 spending categories for each company in the last 30 days, accounting for potential refunds."
• "Given a raw dataset of user login events and transaction timestamps, write a Python script to calculate the average time to first transaction."

Behavioral & Cross-Functional Collaboration

Brex values a diverse team and an inclusive culture where ownership runs deep. This area evaluates how you work with Product Managers, Engineers, and business leaders. Strong candidates demonstrate a history of taking initiative, resolving conflicts through data, and communicating complex technical concepts to non-technical audiences.

Be ready to go over:

• Stakeholder management – Pushing back on flawed product assumptions using data.
• Navigating ambiguity – Taking a vague business question and turning it into a concrete analytical project.
• Impact and leadership – Examples of when your insights directly changed a product roadmap or saved the company money.

Example questions or scenarios:

• "Tell me about a time you had to convince a skeptical Product Manager to change their strategy based on your data."
• "Describe a situation where you had to deliver an analysis with incomplete or messy data."

6. Key Responsibilities

As a Senior Data Scientist at Brex, your day-to-day work is deeply integrated into the lifecycle of our products. You are not operating in a siloed data request queue; instead, you act as a strategic partner. You will spend a significant portion of your time collaborating with Product Managers and Engineers to map out the data infrastructure needed for new features before they even launch.

Your core deliverables will range from designing robust experimentation frameworks to building predictive models that identify customers at risk of churn. You will query massive datasets to uncover hidden patterns in how companies manage their spend, travel, and expenses. When a new product ships, you will be the one defining the success metrics, monitoring the rollout, and presenting actionable insights to leadership.

Furthermore, you will champion data literacy across Brex. This means building intuitive data products, dashboards, and automated reporting tools that empower operations and business teams to make smarter, faster decisions on their own. You will constantly balance deep, exploratory analytical deep-dives with the fast-paced, tactical data needs of a scaling fintech platform.

7. Role Requirements & Qualifications

To be a highly competitive candidate for the Data Scientist position at Brex, you need a blend of deep technical expertise and sharp business intuition.

• Must-have skills:

  • Advanced proficiency in SQL for complex data extraction and transformation.
  • Strong programming skills in Python or R (specifically for data manipulation and statistical modeling).
  • Deep understanding of applied statistics, particularly in the context of A/B testing and causal inference.
  • Exceptional product intuition and the ability to translate business goals into measurable KPIs.
  • Strong communication skills to influence cross-functional stakeholders (Product, Engineering, Risk).

• Nice-to-have skills:

  • Prior experience in the fintech, payments, or B2B SaaS industries.
  • Familiarity with modern data stack tools (e.g., Snowflake, dbt, Looker).
  • Experience with foundational Machine Learning concepts (e.g., classification, regression) to build baseline predictive models.
  • A track record of mentoring junior analysts or shaping data engineering best practices.

8. Frequently Asked Questions

Q: How difficult is the Data Scientist interview at Brex, and how much should I prepare? The process is rigorous and highly competitive. Candidates should expect to spend 1-2 weeks preparing, with a heavy focus on practicing live SQL coding, reviewing A/B testing fundamentals, and structuring product case studies. The difficulty lies in seamlessly blending technical accuracy with strong business sense.

Q: What differentiates a successful candidate from an average one? Average candidates can write the SQL query and compute the math. Successful candidates do that while constantly tying their work back to the customer experience and the company's bottom line. At Brex, product intuition and the ability to communicate "so what?" are what secure offers.

Q: What is the culture like on the Data team at Brex? The culture is fast-paced, highly collaborative, and deeply rooted in ownership. Because data scientists are embedded in specific product or business pods, you are expected to act as a strategic leader within that pod, not just a support function. You will have a high degree of autonomy.

Q: What is the typical timeline from the initial screen to an offer? The end-to-end process generally takes 3 to 5 weeks. Brex moves relatively quickly once the onsite loop is completed, usually providing feedback or an offer decision within a few days of your final interviews.

Q: Is this role fully remote? Brex embraces a flexible working model. While many Data Scientist roles are fully remote across the US, certain specific pods (like Finance-focused roles) may have geographic preferences such as San Francisco, CA. Clarify your specific location requirements with your recruiter early in the process.

9. Other General Tips

• Think out loud during technical rounds: When writing SQL or Python, explain your logic as you type. If you hit a roadblock, communicating your thought process allows the interviewer to guide you, which reflects well on your collaborative skills.
• Clarify the business objective first: Never jump straight into metrics or equations during a product case study. Always start by asking clarifying questions about the target audience, the goal of the product, and the overarching business strategy.

• Structure your behavioral answers: Use the STAR method (Situation, Task, Action, Result) for behavioral questions. Be sure to emphasize the "Action" you specifically took, and quantify the "Result" whenever possible.
• Embrace the Brex product suite: Spend time researching Brex's offerings—corporate cards, expense management, travel software, and global payments. Using accurate terminology and referencing real potential features during your interview shows deep interest and preparation.

10. Summary & Next Steps

Joining Brex as a Data Scientist is an opportunity to shape the future of global B2B payments and spend management. You will be stepping into an environment where data is treated as a first-class product and where your analytical insights will directly influence the trajectory of tens of thousands of companies. The role demands technical excellence, but it rewards you with massive scale, complex challenges, and the ability to drive undeniable business impact.

This module highlights the compensation insights for this role. For a Senior Data Scientist at Brex, the base salary range is typically between $192,000 and$240,000 USD, depending on your exact experience level and location. Keep in mind that this represents the base salary; total compensation packages at Brex are highly competitive and generally include significant equity and comprehensive benefits.

As you move forward, focus your preparation on the intersection of data and product. Sharpen your SQL and Python execution, review your statistical frameworks for experimentation, and practice articulating the business value of your technical decisions. Approach your interviews with confidence—your unique background and problem-solving skills have gotten you this far. For further practice, continue exploring specific interview insights, mock questions, and frameworks on Dataford. You have the potential to excel in this process, so take a deep breath, prepare strategically, and show them the impact you can make at Brex.