Old Mission Capital hires Quant Trader, Software Engineer and Quant Researcher. Candidates report 4 interview stages. Below: what each round tests and how to prepare, the timeline, pay and a 4-week prep plan, drawn from candidate reports and Old Mission Capital's own recruiting pages.
Old Mission Capital interview: quick answer
- Stages4
- Online assessmentTimed - math + coding
- Final roundOnsite: Final rounds - the toughest reported problems
- Pay (candidate-reported)Quant Trader, New grad: $200k - $400k total comp
- RolesQuant Trader, Software Engineer, Quant Researcher
Preparing for Old Mission Capital? Work the rounds in order in the free Old Mission Capital interview funnel, or start with the free online-assessment sample (no signup).
The Old Mission Capital interview process at a glance
| # | Round | Format and length | Prep |
|---|---|---|---|
| 1 | Online Assessment | Timed - math + coding | OA guidePractice |
| 2 | Probability & Mental Math | 45-60 min - video | GuidePractice |
| 3 | ETF, Options & Market-Making Round | 45-60 min - trading intuition | GuidePractice |
| 4 | Onsite Hardest Rounds | Final rounds - the toughest reported problems | Practice |
Stages are listed in the order candidates report them. Formats come from candidate reports and change between cycles, offices and teams; not every candidate sees every stage.
Every Old Mission Capital round: what it tests and how to prepare
1Online Assessment
The process opens with a timed online assessment covering quantitative/probability questions and (for engineering) coding. Speed and accuracy both matter.
Question types: mostly coding and combinatorics, especially greedy, arrays, string algorithms and data structures. Latest candidate report for this round: Jul 2026.
How to prepare
- Move fast and stay accurate -- the OA is timed and gates the loop.
- For SWE: clean, correct code with good complexity.
- Combinatorics + counting show up alongside the coding.
Old Mission Capital online assessment guide →Practice this round (16 questions) →
2Probability & Mental Math
Core probability, expectation, statistics, and mental math under time pressure, with follow-ups. This is the heart of the trading screen.
- Trader technical rounds run 45 to 60 minutes: mental maths, probability, estimation, put-call parity and a live market.
Question types: mostly probability, expectation and statistics, especially discrete probability, conditional probability, independence and expected value. Latest candidate report for this round: Jun 2026.
How to prepare
- Estimate first, then formalize.
- Drill mental math -- fast arithmetic, fractions, and EV.
- Expect follow-ups that extend the problem.
Full Probability & Mental Math guide →Practice this round (40 questions) →
3ETF, Options & Market-Making Round
For trading roles: an ETF fair-value or creation/redemption question, a put-call parity check, options pricing intuition, and a live market where the interviewer trades against you and you re-quote. Kelly sizing and game-theory-flavored decision problems also come up.
- Expect an ETF fair-value or creation and redemption question, a put-call parity check, and a live market where the interviewer trades against you and you re-quote.
Question types: mostly finance, optimization and stochastic processes, especially expected value, portfolio theory, first-passage and stopping times and kelly criterion. Latest candidate report for this round: Jul 2026.
How to prepare
- Price simple options and reason about risk qualitatively.
- Market-making intuition -- quote, get filled, update.
- Kelly / bet sizing under uncertainty.
Full ETF, Options & Market-Making Round guide →Practice this round (18 questions) →
4Onsite: Hardest Rounds
The hardest reported Old Mission problems across every topic -- probability, options/market-making, Kelly sizing, and coding.
- The last round is with senior leadership and includes real fit questions.
Question types: mostly coding, market microstructure and combinatorics, especially expected value, normal distribution, adverse selection and conditional probability. Latest candidate report for this round: Aug 2026.
How to prepare
- Expect the hardest variants -- multi-step probability, market-making under adverse selection, optimal sizing.
- Show trading sense, not just math mechanics.
- Stay sharp under follow-ups -- they push results further.
Practice the Old Mission Capital rounds in order
Each round in the Old Mission Capital funnel has its own practice set, with worked solutions and progress tracking. A free account saves your progress across rounds.
A 4-week Old Mission Capital prep plan
Built from the order of Old Mission Capital's rounds and the topics in each round's practice set. Compress it if your first interview is sooner.
| When | Focus | What to do |
|---|---|---|
| Week 1 | Foundations | Review probability, coding and expectation, the topics that dominate Old Mission Capital's practice sets. Start with Probability course and Quant coding course. Work the easy and medium questions in the Old Mission Capital question set. |
| Week 2 | Early rounds: Online Assessment, Probability & Mental Math and ETF, Options & Market-Making Round | Practice probability, coding and expectation under time pressure, and take the free OA sample (format notes in the OA guide). Add a daily mental-math drill. Talk every answer through out loud; interviewers score the reasoning. |
| Week 3 | Later rounds: Onsite | Move to market microstructure, combinatorics and finance. Rehearse quoting markets with the Make a Market game and read the market-making game guide. Do timed coding sessions in your interview language. Read how quant superdays work. |
| Week 4 | Rehearse the full loop | Run each practice round in order, redo the questions you missed, and prepare two project stories plus a specific answer to "why Old Mission Capital?" (see behavioral questions at trading firms). |
Old Mission Capital pay
| Role | Level | Total comp | Notes |
|---|---|---|---|
| Quant Trader | New grad | $200k - $400k | Base + sign-on + performance bonus. |
| Software Engineer | New grad | $175k - $300k | Strong engineering comp. |
Total compensation means base salary plus bonus and any sign-on, as candidates self-report it. Job postings usually show base salary only, so posted figures and outside salary pages often look lower. Rough ranges, NOT offers. Prop-trading comp is bonus-heavy. Source: Candidate self-reports (levels.fyi, Glassdoor, and candidate forums) -- not employer-verified. Last updated May 30, 2026.
Old Mission Capital teams and what their interviews test
Old Mission hires Quant Traders, Software Engineers, and Quant Researchers. Trading leans on probability, expectation, and options/market-making intuition; engineering adds coding and systems. All share a fast probability + mental-math bar.
| Tracks | What it does | What its interviews test |
|---|---|---|
| Quant Trader Trader | Make markets in options and ETFs. | Probability, expectation, mental math, and options/market-making intuition. |
| Software Engineer Software Engineer | Low-latency trading systems. | Coding, data structures, and algorithms, plus probability. |
| Quant Researcher Quant Researcher | Signal and pricing research. | Probability, statistics, and pricing problems. |
About Old Mission Capital
| Firm type | Proprietary trading firm / ETF-focused market maker (also options) |
|---|---|
| Trading style | Probability + trading intuition + engineering · Market making (low-latency) |
| Founded | 2008 |
| Headquarters | Chicago, IL |
| Other offices | false |
| Capital | Proprietary (private) |
| Employees | ~270 |
| Reported performance | ~$200-400M/yr (est.) |
Founded 2008 in Chicago
Old Mission Capital is a proprietary trading firm that makes markets in options, ETFs, and other instruments. It is a focused, mid-sized Chicago shop with a strong quant + engineering culture.
Culture
A focused Chicago prop shop making markets in options and ETFs. Smaller and less brand-loud than the mega-MMs, with a sharp probability + trading-intuition interview bar and a strong engineering team.
What the interviews feel like
Starts with an online assessment, then several rounds. Expect probability, expectation, and mental math under time pressure, plus options/market-making intuition for trading roles and algorithms for engineers.
Practice for Old Mission Capital on QuantVault
Practice
Courses
Games and drills
Further reading
- How quant superdays work
- Market-making game interview guide
- Mental math for trading interviews
- Behavioral questions at trading firms
- The quant interview process, explained
Similar firms to compare
Firms with a similar business and interview style. Many candidates interview at several of them in the same cycle.
Sources and how this guide is built
- Updated October 20, 2026; firm data last reviewed May 30, 2026; pay last updated May 30, 2026.
- Round detail draws on 90 questions candidates report from Old Mission Capital interviews (the most recent report across all rounds is from Aug 2026). A separate curated Old Mission Capital question set of 68 problems collects the most useful practice for this firm.
- Old Mission Capital's own pages: Old Mission careers.
- Public candidate reports and outside interview guides are cross-checked against each other. Where they disagree the page says "reports differ"; details from a single source are marked as candidate reports.
- No actual interview questions are reproduced on this page. The questions, with worked solutions, are in the practice rounds.
Old Mission Capital interview FAQ
How many rounds are in the Old Mission Capital interview?
Candidates report 4 stages: Online Assessment, Probability & Mental Math, ETF, Options & Market-Making Round, Onsite. The exact number varies by cycle and team.
Is there an online assessment at Old Mission Capital?
Candidates report one: Timed - math + coding. The process opens with a timed online assessment covering quantitative/probability questions and (for engineering) coding. Speed and accuracy both matter.
What happens in the Old Mission Capital final round?
Onsite (Final rounds - the toughest reported problems). The hardest reported Old Mission problems across every topic -- probability, options/market-making, Kelly sizing, and coding.
How much does Old Mission Capital pay?
Candidate-reported total compensation: Quant Trader (New grad) $200k - $400k; Software Engineer (New grad) $175k - $300k. These are self-reported totals including bonus, not offers; job postings usually list base salary only.
How should I prepare for the Old Mission Capital interview?
Prepare round by round over about four weeks: foundations first, then the early rounds (Online Assessment, Probability & Mental Math, ETF, Options & Market-Making Round), then the later rounds, then a full rehearsal. Each round has its own practice set on QuantVault, and the online assessment has a dedicated guide.
What does Old Mission Capital do?
Old Mission Capital is a proprietary trading firm / ETF-focused market maker headquartered in Chicago, IL. Old Mission Capital is a proprietary trading firm that makes markets in options, ETFs, and other instruments. It is a focused, mid-sized Chicago shop with a strong quant + engineering culture.
Is Old Mission an options shop or an ETF shop?
Mainly an ETF specialist. Expect questions on ETF fair value and the creation and redemption process as well as options.
Is there a market-making game at Old Mission?
Recent outside reports both describe interviewer-run market-making games, while an older QuantVault summary said there was no scripted game. Prepare to quote a live market.
Do Old Mission traders have to code?
A little. The trader online test includes a short Python piece.
Start preparing for Old Mission Capital
Open the interactive Old Mission Capital interview funnel: every stage with its practice set, from the first screen to the final round. Create a free account to save your progress.