The Susquehanna (SIG) interview process for quantitative traders is an online problem-solving test on Mercer Mettl (17 questions in 60 minutes), a recruiter call with a surprise probability question, one or two 60-minute technical interviews with a senior trader, and an in-person Super Day of expected value games, market making, a group bidding game and an HR interview. Every trading round tests probability, expected value and decisions under uncertainty, and the math is done out loud. Software developers follow a different loop: a coding OA, a recruiter call, a data structures and algorithms interview, and a final round on object-oriented design and behavioral questions.
SIG is an options market maker and quantitative trading firm founded in 1987 and based in Bala Cynwyd, Pennsylvania. Games are part of how it trains traders: its site says poker teaches decision-making under uncertainty, and the card game Wizard is used to introduce candidates to gaming at SIG.
Susquehanna (SIG) interview process
- Problem Solving Assessment (trading)60 min
- Coding OA (software)Timed
- Recruiter call20-45 min
- Technical interviewAbout 60 min
- Super DayMost of a day
| Round | Duration | What it tests |
|---|---|---|
| Problem Solving Assessment (trading) | 60 min | 17 free-response questions: continuous probability, expected value, combinatorics, calculus, logic |
| Coding OA (software) | Timed | Data structures and algorithms; CodeSignal in one 2025 report |
| Recruiter call | 20-45 min | Resume, why SIG, markets, at least one probability question asked without warning |
| Technical interview | About 60 min | Probability, expected value, Markov chains (trading); DSA and trade-offs (software) |
| Super Day | Most of a day | EV games and market quoting, a group bidding game, HR; for developers, OOP and team-matching technicals |
Susquehanna (SIG) interview questions with answers
Q: You roll a die and may reroll once, keeping the second roll. What is the expected payout?
Work backward. If you reroll, you get 3.5 on average, so keep any first roll above 3.5: keep 4, 5 or 6. Expected value = (4 + 5 + 6)/6 + (3/6) x 3.5 = 2.5 + 1.75 = 4.25. With two rerolls, the threshold for the first roll becomes the value of the one-reroll game, 4.25, so keep only 5 or 6: (5 + 6)/6 + (4/6) x 4.25 = 1.833 + 2.833 = 4.67. SIG interviewers often follow up by asking what you would pay to play, which is the expected value minus whatever edge you want.
Q: Gambler’s ruin: you start with i dollars and bet 1 dollar each round until you hit 0 or N. What is the chance you reach N?
For a fair game, the chance is i/N, because your bankroll is a martingale and its expected final value i must equal N times the success probability. For a biased game where you win each round with probability p and lose with q = 1 - p, the chance is (1 - (q/p)^i) / (1 - (q/p)^N). A useful follow-up is the expected duration of the fair game, i(N - i).
Q: Make a market on the sum of three dice.
The mean is 3 x 3.5 = 10.5 and the variance is 3 x 35/12 = 8.75, so the standard deviation is about 2.96. Quote a two-sided market around 10.5, for example 10 bid at 11 offered, and explain that the width reflects your uncertainty and the risk of trading against someone who knows more. As the interviewer trades with you or reveals a die, update: if one die shows 6, the new mean is 6 + 7 = 13. Track your position and shade your quotes to reduce inventory, which is the market-making skill SIG cares about.
Q: A coin is either fair or two-headed with equal prior. It lands heads three times. What is the chance it is two-headed?
Bayes: P(three heads | two-headed) = 1 and P(three heads | fair) = 1/8. Posterior = (0.5 x 1) / (0.5 x 1 + 0.5 x 1/8) = 1 / (1 + 1/8) = 8/9. The chance the next flip is heads is 8/9 x 1 + 1/9 x 1/2 = 17/18. Give answers as fractions; the SIG assessment can mark decimals wrong.
Q: In the AKQ poker game, how should each player play?
A prep-guide staple used to test SIG-style thinking. Each player antes 1 (pot of 2), player 1 gets one of A, K or Q and may bet 1 or check, and player 2 holding another card calls or folds. Player 1 always bets the A for value and checks the K. Player 1 bluffs the Q at a rate that makes player 2 indifferent with the K: calling risks 1 to win 3, so the bluff-to-value ratio is 1 to 3 and the Q bets one-third of the time. Player 2 calls with the K one-third of the time, which makes player 1’s Q bluff break even. The point is sizing bluffs and calls to the pot odds.
Q: Count how many times the digits 0, 1 and 4 appear when writing every number from 0 to n.
Do not loop to n for large inputs. For a digit d and each place value p = 1, 10, 100, …, split n into high = n / (10p), cur = (n / p) mod 10 and low = n mod p. Occurrences of d at that place are high x p, plus p if cur is greater than d, plus low + 1 if cur equals d. For d = 0, subtract the leading-zero cases: use (high - 1) x p instead of high x p when high is at least 1, and skip the place entirely when high is 0; then add 1 for the number 0 itself. That is O(log n) per digit. Test against a brute force for n up to 10,000.
Q: State put-call parity and use it.
For European options on a non-dividend stock with the same strike K and expiry T, C - P = S - K e^(-rT). If the left side is too high relative to the right, sell the call, buy the put and buy the stock, financing at rate r, to lock in the difference. Interviewers use it to check you can spot a mispricing quickly; with r near zero and short expiry, C - P is about S - K.
Susquehanna interview questions by role
| Role | Reported questions and topics |
|---|---|
| Quantitative trader | Gambler’s ruin, random walks, grid path counting, calculus optimization, Bayes, seating and age logic puzzles (assessment); conditional probability and EV (phone); dice, card and coin EV games, market quoting, auction board game (Super Day) |
| Trader, Chicago | Options questions; valuing an option (2025 Glassdoor reports) |
| Trader, Dec 2024 | Three probability questions on Bayes’ theorem, the law of total probability and expectation |
| Software developer | DSA with trade-offs; optimize given code with hash maps; OOP design; digit-counting from 0 to n; probability in some finals |
| Quant research | Statistics, probability and coding (no detailed public reports found) |
SIG quantitative trader interview
SIG’s trading track is the one most candidates mean by “the SIG interview.” TraderMath’s guide gives the most detailed public breakdown:
Problem Solving Assessment. 60 minutes, 17 free-response questions of rising difficulty on Mercer Mettl, covering continuous probability, expected value, combinatorics, calculus and deductive logic. You can go back and flag questions. Answers must be integers or fractions, since decimals may be marked wrong. A calculator, pen and paper are allowed, the link must be started within seven days, and switching tabs can end the test. A shorter 20-minute Quantitative Evaluation with no going back still appears but less often; Extern describes a roughly 20-minute Mettl test for internship applicants.
Recruiter phone call. Resume, motivation and why SIG (game theory, poker, options market making), current markets, and at least one probability or expected value question asked conversationally without warning. Do the math out loud.
Technical interview. About 60 minutes on video, usually with a senior trader, mostly probability and expected value with Markov chains coming up regularly. Usually two rounds, sometimes one; strong candidates are occasionally moved straight to the final.
Super Day. In person. About an hour of expected value games with cards, dice or coins, followed by quoting a market around them; a physical board game played with other candidates built on auctions and bidding; and a 30-minute HR interview on why trading, why SIG, weaknesses and your edge. Fast mental arithmetic is expected at this stage, and some roles add put-call parity and basic options intuition.
Does SIG play poker in the interview?
SIG’s own game theory page says poker is used to teach new traders decision-making under uncertainty, that World Series of Poker bracelet winners Bill Chen and Jerrod Ankenman (co-authors of The Mathematics of Poker) work at the firm, and that the trick-taking card game Wizard is used to introduce candidates to gaming. It lists decision-science traps traders are trained to avoid: confirmation bias, anchoring, availability bias and framing.
Whether poker is an interview round is not settled. TraderMath says poker is taught after joining and needs no background. A techinterview.org article describes a no-limit hold’em session during Super Day or a separate evening. Prepare for poker-style questions on pot odds and bet sizing relative to your edge, but do not spend weeks learning hold’em strategy.
SIG software developer interview
SIG’s technology roles have their own loop with little poker. 2025 Glassdoor and Dataford reports describe:
- A timed coding online assessment, on CodeSignal in one report.
- A recruiter screening call.
- A technical interview on data structures and algorithms and explaining trade-offs; one reviewer had 90 minutes. Another was handed existing code and given 30 minutes to optimize it, which came down to using hash maps.
- A final round on object-oriented programming concepts and behavioral questions, with probability questions in some reports. A December 2025 candidate near Philadelphia was told the final day has an onsite technical interview followed by three or four team-matching technical interviews.
SIG’s Dublin graduate posting asks for an understanding of algorithms, data structures and object-oriented design patterns. A Dublin candidate in October 2025 noted you can choose to solve first and then explain, or explain as you go. TraderMath also records a two-hour coding exercise: count how often the digits 0, 1 and 4 appear when writing every number from 0 to n.
SIG quantitative research interview
Prep sites agree that quant research goes deeper into statistics and probability than the trading loop and adds a real coding component, but SIG does not publish the process and TraderMath’s guide covers trading only. Treat the research loop as the trading math plus statistics, regression and a coding round, and ask your recruiter for the format.
Who does well in SIG interviews
Good fit: You do probability in your head and out loud, you like games and can explain why a bet is good in expected value terms, and you change your mind quickly when new information arrives. For developers, you write clean object-oriented code and can explain trade-offs as you go.
Harder path: You know formulas but freeze when a probability question arrives mid-conversation on the recruiter call. SIG’s values put “good decision making” first, and interviewers watch how you reason under uncertainty more than whether you recall a textbook result.
A four-week SIG prep plan
- Week 1: Probability foundations: conditional probability, Bayes, expectation, combinatorics on grids, gambler’s ruin. Do one 60-minute, 17-question timed set and give answers as fractions.
- Week 2: Expected value games and Markov chains: dice reroll games, coin-flip stopping problems, absorbing chains. Practice explaining each answer out loud in under two minutes.
- Week 3: Market making: quote two-sided markets on dice sums, card draws and estimates; have a friend trade against you and reveal information. Add mental arithmetic drills daily. Read SIG’s decision-science page on anchoring and confirmation bias.
- Week 4: Super Day simulation: an hour of EV games, a group auction game with friends, and a 30-minute “why trading, why SIG” interview.
Software developer track: replace weeks 2 and 3 with timed coding sets, one OOP design problem a day, and optimizing a slow function you did not write.
SIG pay in the US
SIG says it does not post salary ranges externally, and its Bala Cynwyd ads leave pay out. TraderMath’s September 2026 review of SIG’s New York ads for 2027 lists a $300,000 base for Master’s and PhD quantitative researchers and systematic traders, and $8,600 a week for Master’s and PhD quant research and systematic trading interns over a ten-week New York program, with a signing bonus, housing and meals.
Software developer pay is less clear. TraderMath’s summary of US salary filings from July 2025 to June 2026 shows median filed ranges of $88,100 to $222,000 for “Software Developer” and $180,000 to $265,000 for “Software Developer - Mid.” For software interns, Extern cites about $69 an hour plus a $10,000 sign-on bonus, while Levels.fyi lists a self-reported Summer 2026 Bala Cynwyd software intern at $150 an hour; the gap is large, so confirm with your recruiter.
Frequently asked questions about Susquehanna interviews
What is the Susquehanna (SIG) interview process for quantitative traders?
TraderMath describes four stages: an online problem-solving assessment on Mercer Mettl (17 free-response questions in 60 minutes on probability, expected value, combinatorics, calculus and logic), a recruiter phone call with at least one probability or expected value question, one or two 60-minute video interviews with a senior trader, and an in-person Super Day with expected value games, quoting a market, a group bidding board game and a 30-minute HR interview.
What are common Susquehanna interview questions?
For trading: gambler’s ruin, random walks, grid path counting, Bayes’ theorem, expected value games with dice, cards or coins, Markov chains, quoting a bid and ask on an uncertain quantity, and for some roles put-call parity or valuing an option. For software developers: data structures and algorithms, object-oriented design, optimizing a given piece of code (one report involved hash maps), and in one reported exercise counting how often digits 0, 1 and 4 appear when writing every number from 0 to n.
Does SIG play poker in interviews?
Sources disagree. SIG’s own site says it uses poker to teach new traders decision-making under uncertainty and that WSOP bracelet winners Bill Chen and Jerrod Ankenman work there, and it uses the card game Wizard to introduce candidates to gaming. TraderMath says poker is taught after you join and is not an interview round, while another prep site describes a no-limit hold’em session at Super Day. Expect poker-style expected value and bet-sizing questions either way; you do not need poker experience.
What is the SIG software developer interview process?
2025 reports describe a coding online assessment (CodeSignal in one report), a recruiter call, a technical interview on data structures, algorithms and trade-offs (90 minutes in one report), and a final round covering object-oriented programming, behavioral questions and sometimes probability. A December 2025 Philadelphia-area candidate was told the final day includes an onsite technical interview followed by three or four team-matching technical interviews.
How much does SIG pay?
SIG says it does not post salary ranges externally, and its Bala Cynwyd ads omit pay. TraderMath’s September 2026 review of SIG’s New York ads for 2027 lists a $300,000 base for Master’s and PhD quantitative researchers and systematic traders, and $8,600 a week for Master’s and PhD quant research and systematic trading interns. Filed US base ranges for the Software Developer title ran from $88,100 to $222,000 in July 2025 to June 2026.
How long does the SIG hiring process take?
TraderMath puts the trading process at two to eight weeks, most often two to four, with about a week between rounds and offers one to two weeks after the final stage. US summer internships post 11 to 12 months ahead; Summer 2026 roles appeared in June 2025.
What are the rules on the SIG online assessment?
For the trading problem-solving test, TraderMath reports answers must be integers or fractions (decimals may be marked wrong), a calculator, pen and paper are allowed, you can move back and flag questions, the link must be started within seven days, and switching browser tabs can end the test.
Sources
- SIG: about Susquehanna (values and business lines)
- SIG: game theory and decision science
- TraderMath: SIG interview guide (trading track)
- TraderMath: SIG salaries from job ads and filings
- techinterview.org: how Susquehanna interviews traders
- Extern: Susquehanna internship guide
- Wikipedia: Susquehanna International Group
- Software developer loop and trader question reports: Glassdoor SIG interview reviews from December 2024 to December 2025 (Chicago, Philadelphia, Dublin, Sydney) and a Dataford SIG software engineer experience summary
- Levels.fyi SIG software engineer intern entries (Summer 2026, Bala Cynwyd)