Senior Data Scientist, Prenatal

Join a team of brilliant, passionate innovators determined to transform healthcare. At BillionToOne, we've built a category-defining, publicly traded company on Nasdaq where transparency fuels trust, collaboration drives breakthroughs, and every contribution moves the needle on our mission to make life-changing diagnostics accessible to all. We don't just aim for incremental improvements; we build products that are 10x better than anything that exists today.

Our scientists, engineers, sales executives, and visionaries are united by an unwavering commitment to changing the standard of care in prenatal and cancer diagnostics. This is where cutting-edge science meets human compassion, and every innovation you contribute helps remove the fear of the unknown from some of life's most critical medical moments.

If you're driven by purpose, energized by innovation, and ready to help shape the future of precision medicine at scale, this is where you belong.

We are looking for a Senior Data Scientist to join our Prenatal data team. At BillionToOne, our data scientists are full-stack: we own the entire analytics value chain. That means wearing a data engineering hat to land data into our central warehouse, an analytics engineering hat to model, document, and test it, and a data science hat to analyze it, build dashboards, and deliver insights that drive decisions across the company.

This is a high-impact, high-autonomy role. You will work directly with stakeholders across the business — commercial teams, lab operations, clinical and quality teams, bioinformatics, and executive leadership — owning those relationships end-to-end. AI is woven through how we work: you will use it daily to accelerate your own analyses and engineering, build HIPAA-compliant AI-powered analysis workflows for the team, and help colleagues across the organization adopt AI to do their best work.

• →Own the full analytics stack for Prenatal: ingest data from disparate sources into our central data warehouse, build clean and well-tested data models, and deliver analyses, dashboards, and tooling that stakeholders can use directly.
• →Partner with stakeholders across the business to answer high-stakes questions with data — for example, helping the lab improve turnaround time, helping sales identify at-risk accounts and new business opportunities, supporting clinical affairs with data on samples and outcomes, supporting business metrics around new product launches, and informing executive decisions on growth and strategy.
• →Build and maintain the central analytical data warehouse that aggregates data from across the organization, while partnering with teams who own their own operational systems (e.g., Clarity, bioinformatics pipelines).
• →Use AI tools to accelerate your own work, build HIPAA-compliant AI-powered analysis workflows, and help colleagues across the company adopt AI to improve their productivity.
• →Develop and maintain Tableau dashboards and self-serve analytics that turn data into action for clinical, commercial, and operational teams.

• 3+ years of experience in a data science, analytics engineering, or related data role. More experience is welcome.
• Strong proficiency in SQL and Python (or R) for data manipulation and analysis.
• Comfort working with messy, disparate data sources and the judgment to know when to clean, when to re-model, and when to push upstream.
• Experience working with clinical, healthcare, or other regulated data.
• Hands-on experience using AI tools to enhance your work, and an interest in helping others do the same.
• Excellent communication skills and the ability to partner directly with non-technical stakeholders to scope problems and deliver useful answers.
• A strong sense of ownership: you are comfortable working directly with stakeholders and treat data quality and stakeholder outcomes as part of your job.

• Familiarity with any of the tools we use is a plus: dbt, Airflow, Tableau, Stitch, Hightouch, Cursor, Claude, ChatGPT, AWS (S3, Batch, RDS, MWAA), and Clarity.
• Familiarity with bioinformatics, molecular diagnostics, or the broader healthcare landscape — including the lab sales cycle, prior authorization, and reimbursement — is also a plus, as is a background in the biosciences.

Unity Complete™ is the only non-invasive prenatal screen capable of assessing fetal risk for both common recessive conditions and aneuploidies from a single maternal blood sample. Our Northstar® liquid biopsy test uniquely combines treatment selection with real-time monitoring, giving oncologists unprecedented precision in cancer care.

From $0 to $150M+ in Annual Recurring Revenue in just five years. In 2025, we completed one of the most successful IPOs for a medical diagnostics company, building on nearly $400M in private funding,including our $130M Series D in 2024 and backed by world-class investors including Hummingbird, Adams Street Partners, Neuberger Berman, Baillie Gifford, and Premji Invest.

Forbes named us one of America's Best Startup Employers for 2025 and we're Great Place to Work certified, with 100% of our people willing to go the extra mile, even as we've scaled to over 700 employees.

Headquartered in Menlo Park with facilities in Union City, CA, and a new lab opening in Austin, TX in 2027, we're continuing to push the boundaries of what's possible in molecular diagnostics. We're just getting started.

Ready to help us change the world, one molecule at a time? Learn more at billiontoone.com