Milliman Software Engineer interview questions & guide 2026

To succeed in the Milliman interview process, you must be prepared for a blend of core computer science fundamentals, practical software engineering scenarios, and behavioral questions that assess your communication clarity. The following questions are representative of what candidates face across various Milliman offices.

Object-Oriented Programming (OOP) & Core CS

These questions assess your foundational understanding of software design principles, memory management, and execution models.

• Explain the four pillars of Object-Oriented Programming and provide a real-world example of how you have used encapsulation to protect state in a recent project.
• How does recursion work under the hood? Explain this concept as if you were explaining it to your grandmother.

Preparing for an interview at Milliman requires a dual focus on deep technical execution and strong communication. You must show that you can not only write high-quality code but also explain why your solution is correct and how it fits into the broader business ecosystem.

Role-Related Knowledge – You must demonstrate a commanding grasp of Object-Oriented Programming principles and database design. Depending on the team you interview with, deep familiarity with either C# / .NET or Java is highly valued. You should be prepared to discuss language-specific memory management, concurrency models, and framework best practices.

Problem-Solving & Testability – Milliman engineers care deeply about edge cases and validation. When writing code—whether on a whiteboard, in an online text editor, or during a take-home test—always write unit tests. You must show that you proactively think about how to break your own code and how to validate its correctness under extreme inputs.

Communication & Simplification – Because you will work alongside actuaries, quantitative analysts, and business consultants, your ability to translate highly technical engineering concepts into plain English is a critical hiring signal. Practice explaining complex algorithms, system designs, or architectural trade-offs simply and concisely.

Ownership & Professional History – Expect to be grilled on the details of your resume. You should be prepared to explain the business impact, technical details, and team dynamics of every past role listed. Be ready to own both your successes and the lessons learned from project failures.

The interview process at Milliman is thorough and designed to evaluate both your immediate technical capabilities and your long-term alignment with the team's engineering standards. Because Milliman operates as a decentralized network of practices, the exact sequence of steps can vary depending on the specific office and team (e.g., Seattle, Chicago Trading, or Brookfield). However, most candidates experience a structured progression that tests core skills before moving to intensive onsite evaluations.

The journey typically begins with an initial recruiter screen to align on your background, technical stack preferences, and compensation expectations. This is followed by a technical screening phase, which may consist of a technical video call with a senior developer, an online coding assessment, or a take-home programming test (such as building a console application to process data).

If you pass the screening stage, you will be invited to a comprehensive final round. Historically, this has been an intensive in-person or virtual loop lasting between three and four hours. During this loop, you will meet with multiple small panels or pairs of engineers, engineering managers, and architects. These sessions cover deep-dive technical definitions, live coding or system design, project retrospectives, and behavioral discussions.

This visual timeline outlines the typical progression from your initial application to the final hiring decision. You should interpret this as a guide to pacing your preparation: focus on core CS definitions and basic coding for the initial screens, and save your deep-dive system architecture and behavioral storytelling practice for the final loop. Note that some offices may bypass the take-home test in favor of live-paired programming sessions during the final round.

Object-Oriented Design & Architecture

At Milliman, software must be maintainable, extensible, and robust enough to handle complex calculations over decades of product lifecycles. Interviewers will evaluate your ability to design systems using clean, object-oriented paradigms.

Be ready to go over:

• Design Patterns – When and how to apply patterns like Factory, Strategy, Singleton, and Observer to solve real-world design problems.
• SOLID Principles – A deep, practical understanding of how to write modular code that is easy to test and refactor.

As a Software Engineer at Milliman, your day-to-day responsibilities will vary depending on your practice group, but they generally encompass the following core areas:

• Designing and Developing Core Software – You will write clean, maintainable, and highly performant code to build financial modeling systems, healthcare analytics platforms, or risk assessment tools. You will ensure your systems are scalable, secure, and capable of processing large-scale computations.
• Collaborating with Domain Experts – You will work closely with actuaries, financial consultants, and quantitative analysts. You will translate complex mathematical formulas, regulatory requirements, and business logic into high-performing software algorithms.
• Ensuring Code Quality and Test Coverage – You will take ownership of the quality of your deliverables by writing robust unit, integration, and regression tests. You will participate in rigorous code reviews, ensuring that the team's architectural standards are upheld.
• Optimizing Data Pipelines and Databases – You will design, implement, and optimize database schemas, queries, and data ingestion pipelines to ensure fast, reliable access to critical financial and health data.
• Maintaining and Modernizing Legacy Systems – Many of Milliman's core calculation engines are highly sophisticated and have been refined over years. You will be responsible for maintaining these critical systems while systematically refactoring and modernizing them for cloud environments.

To be competitive for a Software Engineer position at Milliman, you should possess a strong foundation in computer science and a practical, quality-first approach to software development.

Technical Skills

• Must-have skills:

  • Proficiency in at least one major object-oriented programming language, such as Java, C#, or C++.
  • Strong relational database skills, including advanced SQL querying, schema design, and query optimization.
  • Demonstrated experience with unit testing frameworks (e.g., JUnit, NUnit) and writing highly testable code.
  • Solid understanding of core data structures, algorithms, and software design patterns.

• Nice-to-have skills:

  • Experience with cloud platforms, particularly Microsoft Azure or AWS.
  • Familiarity with modern front-end frameworks like React or Angular for full-stack roles.
  • Knowledge of data processing tools and frameworks (e.g., Python, Spark, or pandas).
  • Background or interest in financial services, actuarial science, quantitative finance, or healthcare analytics.

Experience & Soft Skills

• Experience level: Typically requires a Bachelor's degree in Computer Science, Software Engineering, Mathematics, or a related quantitative field. Prior professional experience as a software engineer is highly valued, particularly in environments that demand high numerical precision and rigorous data processing.
• Soft skills:
  • Exceptional communication skills, with the ability to explain complex technical designs to non-technical business partners.
  • A strong sense of ownership, attention to detail, and a disciplined approach to code quality and documentation.
  • Collaborative mindset, comfortable working in small, autonomous teams where developers wear multiple hats.

Q: How difficult are the technical interviews at Milliman? A: Candidates generally rate the difficulty as average to difficult. The challenge rarely comes from obscure, competitive-programming brain teasers. Instead, the difficulty lies in the depth of foundational knowledge required. You must be able to explain core CS concepts (like OOP, recursion, and SQL indexing) with absolute precision and demonstrate a disciplined approach to testing your own code.

Q: What is the typical timeline from the initial screen to an offer? A: Because Milliman is decentralized, the timeline can vary significantly by office. Some candidates complete the entire process in two to three weeks, while others experience a slower progression over four to six weeks. It is highly recommended to maintain active communication with your recruiter and follow up if you do not receive updates within a week of an interview.

Q: How much do they focus on system design versus coding? A: This depends on your seniority. For junior to mid-level roles, the focus is heavily on core coding, OOP principles, SQL queries, and unit testing. For senior, lead, or architect roles, expect multiple sessions dedicated to system design, cloud architecture, scalability, and scenario-based software design.

Q: What is the work culture and remote policy like for engineers? A: Milliman offers a professional, stable, and intellectually stimulating work environment. The work-life balance is generally highly respected compared to high-intensity tech startups. Remote and hybrid work policies are determined at the office or practice level; many teams operate on a hybrid schedule, requiring a few days in the local office, while some positions are fully remote.

• Clarify the Tech Stack Early: Because Milliman's offices operate independently, one team might be a dedicated C#/.NET shop while another is purely Java or C++. Ask your recruiter during the initial call which technologies the team uses so you can tailor your language-specific preparation.

• Over-Communicate During Coding Sessions: When completing a live coding exercise or discussing a design, talk through your thought process. Explain the trade-offs of your approach, why you chose a specific data structure, and how you plan to handle potential edge cases.

• Prepare Your Professional Narrative: If you are interviewing at an office that uses the Topgrading methodology (such as Brookfield or Milwaukee), spend time reviewing your resume chronologically. Be ready to discuss your managers, your specific contributions, and the exact reasons for your career transitions.

• Ask Smart, Office-Specific Questions: Use the end of your interviews to learn about the specific practice group's business model. Ask about how they collaborate with actuaries, how they manage their release cycles, and what the primary scaling challenges are for their specific product line.

A Software Engineer role at Milliman offers a unique opportunity to build high-precision, highly impactful software that sits at the intersection of technology, finance, and healthcare. It is a career path that rewards technical discipline, architectural clean-coding, and strong cross-functional communication. By focusing your preparation on core computer science definitions, practical coding, testability, and clear behavioral storytelling, you can position yourself as a standout candidate.

As you prepare to take the next steps in your interview journey, remember to treat the process as a mutual evaluation. Use your conversations with the engineering team to understand the specific challenges, technologies, and culture of the practice group you are interviewing with. For more real-world interview experiences, detailed company insights, and preparation resources, you can explore additional guides on Dataford.

The salary information above highlights the competitive compensation structure at Milliman. When evaluating an offer, remember that compensation packages often include a base salary coupled with performance-based bonuses tied directly to the profitability of your specific practice group. Use this data to benchmark your expectations based on your location and experience level as you enter final-round discussions.