EY Case Interview: Choose Consulting, S&T or EY-Parthenon

EY is not one interview. Start with the service line named on your invitation: prepare operations and implementation for EY Consulting, transaction logic and deal math for Strategy & Transactions, and strategy or diligence for EY-Parthenon. The exact rounds and case format vary by role, office, and recruiting cycle, so the invitation and recruiter outrank any generic guide.

Which EY division are you interviewing for?

Choose your lane before you choose your cases. The table separates stable service-line focus from candidate-reported interview patterns; none of the format labels is a universal EY rule.

EY Consulting covers technology, operations, cybersecurity, supply chain, and transformation work. Practice structuring practical business problems and implementation trade-offs, while remembering that EY does not publish one Consulting case format.

EY Strategy & Transactions (S&T) covers deal-oriented work such as M&A advisory, diligence, valuations, modeling, and restructuring. Acquisition logic and financial reasoning are relevant practice priorities when the role or invitation points toward a deal exercise.

EY-Parthenon is EY's strategy arm (formerly Parthenon Group, acquired in 2014), with corporate-strategy and commercial-diligence work. Candidate-led, written, and presentation exercises are reported in some processes, but they are not universal. For a deeper role-specific review, read the EY-Parthenon case interview guide.

What can the EY interview process include?

EY officially describes a role-dependent recruiting process, while public candidate reports show meaningful variation by country, office, level, and service line. Treat the sequence below as a menu of possible components, not a promised order.

EY Interview Process (All Divisions)

1. 01

   Application & Screening. Official: EY reviews applications against the role. Program-specific: some regions and early-career programs use online assessments or job simulations; prepare for them only when the portal or invitation confirms them.

2. 02

   Interview stage. Possible components include behavioral questions, a case, a scenario discussion, or a technical conversation. Candidate reports describe both guided and open cases; the invitation controls.

3. 03

   Additional interviews. Some processes add further behavioral, case, data, or deal discussions. Complexity and sequencing depend on the role and office.

4. 04

   Written or presentation exercise. Candidate reports describe data-packet, presentation, or written exercises in some EY-Parthenon and S&T processes. Prepare this only when the invitation or recruiter confirms it.

5. 05

   Later Interviews. Candidate-reported: some processes add senior interviews, a written case, presentation, or group exercise. The number, timing, and format vary; confirm the components on your invitation.

6. 06

   Offer Decision. Timing varies by office, level, and recruiting channel. Ask your recruiter what decision timeline applies to your process.

If your invitation confirms an online stage, use the EY online assessment guide. Do not divert case-prep time to an assessment that is not part of your process.

Use the work, not an assumed format, to choose your practice:

• EY Consulting: prioritize operations, technology, implementation trade-offs, and stakeholder-aware recommendations.
• EY S&T: prioritize acquisition logic, downside risks, multiples, synergies, and the strategic rationale for a transaction.
• EY-Parthenon: prioritize market entry, growth strategy, and commercial diligence. Candidate reports mention several formats, so verify yours in the EY-Parthenon guide and with the recruiter.

How should you prepare if your EY invitation says interviewer-led?

One thing to settle first: published guides disagree on whether EY uses interviewer-led or candidate-led cases. Some prep sites describe EY cases as candidate-led (you drive the analysis like at Bain or BCG), while others describe EY Consulting cases as interviewer-led and structured. Both can be true, because the format depends on the division, the office, and the interviewer. The practical takeaway is to prepare for both styles. If you can only drive an open case but freeze when an interviewer hands you a sequence of guided prompts, you are exposed.

In an interviewer-led case, the interviewer controls the pace and supplies a sequence of prompts. The example below teaches that format; it is not a claim that every EY Consulting case works this way.

Illustrative guided-case flow:

1. Prompt: "Our client is a mid-size hospital system experiencing a 15% increase in patient wait times over the past year. What might be driving this?"
2. Follow-up: "We've identified that the bottleneck is in the discharge process. What factors could slow discharge?"
3. Data question: "Here's a table showing average discharge times by department. What do you notice?"
4. Recommendation: "Given your analysis, what would you recommend the client do?"

This differs from a more open case in which the candidate drives the analysis. Practice both initiating a decision path and responding coherently to guided prompts when your invitation does not confirm the format.

One risk in a more guided case is passivity: answering each question in isolation without connecting the pieces. Reference earlier evidence when it matters: "This connects to the staffing data we looked at earlier, which showed..." That creates a single argument rather than a set of disconnected responses.

How should you practice deal-oriented EY S&T cases?

If your S&T invitation includes a case, deal-oriented practice should combine financial and strategic reasoning. The themes below mirror the work, not a guaranteed EY S&T question bank.

Useful S&T practice prompts:

• Should our client acquire this target? At what price?
• A PE fund is evaluating a portfolio company. What are the value creation levers?
• The client is considering divesting a business unit. Should they?
• Restructuring: the client is overleveraged. What are the options?

Skills these practice prompts develop:

• Can you assess whether a deal creates value?
• Do you understand basic valuation concepts (multiples, DCF logic, synergies)?
• Can you identify risks in a transaction?
• Do you connect financial analysis to strategic rationale?

You do not need investment banking-level modeling skills. But you should be comfortable with EBITDA multiples, revenue synergy logic, and the difference between strategic and financial buyers. Review the profitability framework for the financial decomposition skills that transfer directly to S&T cases.

Fictional Worked Case Example: EY Consulting, Operations Improvement

All figures below are supplied assumptions for this fictional practice prompt.

Prompt: "Our client is a national logistics company. On-time delivery rates have dropped from 94% to 87% over the past 18 months, and their largest customer (30% of revenue) is threatening to switch providers. How would you diagnose and fix this?"

Step 1: Structure the diagnosis: "I'd break the on-time delivery problem into three areas: network capacity (are there bottleneck routes or hubs?), operational execution (are drivers, vehicles, or scheduling systems underperforming?), and demand changes (has volume or delivery mix shifted in a way the network wasn't built for?)."

Step 2: Interviewer provides data: The interviewer shares that total delivery volume grew 22% over 18 months, but fleet size only grew 8%. Average route load factor increased from 78% to 93%.

Step 3: Quantitative analysis:

• Volume per vehicle index: 1.22 / 1.08 ≈ 1.13, so average volume per vehicle rose by roughly 13% under the supplied assumptions.
• Load factor rose from 78% to 93%, an increase of 15 percentage points or roughly 19% relative to the starting level.

These figures support a capacity-pressure hypothesis, but they do not prove the root cause. Route mix, hub bottlenecks, labor availability, maintenance, scheduling, and service-window changes could also explain the decline.

Step 4: Recommendation: "I would first diagnose delays by route, hub, time window, and failure cause, then test whether alternative service windows reduce peak pressure for the largest customer. Before sizing fleet expansion, I would request route-level capacity, carrier and vehicle costs, customer revenue and margin, and churn probability. Those inputs determine whether owned vehicles, contracted capacity, process changes, or a combination creates the best risk-adjusted response."

Worked Case Example: EY S&T, Acquisition Evaluation

This is a fictional practice case. Every clinic count, price, growth rate, margin, and market-share figure below is supplied for the exercise.

Prompt: "A PE fund is considering acquiring a regional chain of 28 veterinary clinics for $120M. Should they proceed?"

Structure: "I'd evaluate this across three areas: market attractiveness of the veterinary services industry, competitive position of the target, and financial return at $120M."

Key analysis (with numbers):

The interviewer supplies these assumptions: the 28 clinics generate $5.2M average revenue each ($145.6M total), EBITDA margins are 20%, the market grows at 9% annually, and the top five consolidators hold 15% market share. These figures belong to the prompt; they are not claims about the current veterinary-services market.

• Total EBITDA: $145.6M x 20% = $29.1M
• Implied multiple: $120M / $29.1M = 4.1x EBITDA
• Market growth: 9% annually, well above GDP
• Fragmentation: top 5 hold only 15%, significant consolidation opportunity

"At 4.1x EBITDA, the entry valuation merits deeper diligence, but the prompt does not provide enough evidence to call it attractive. I would request comparable transactions, clinic-level retention and margin data, debt assumptions, integration costs, and a downside case before estimating returns."

Recommendation: "Proceed to detailed diligence, focused first on veterinarian retention and clinic-level revenue concentration, then on the realistic acquisition pipeline, integration cost, and downside return. The evidence, not a preset risk ranking, should determine the deal breaker."

Behavioral Questions Across EY Divisions

Behavioral questions appear across candidate reports, but EY does not publish one firm-wide weighting. Prepare collaboration, client service, integrity, ambiguity, and motivation stories because they are relevant to the work and adaptable to several interview formats.

Frequently asked EY behavioral questions:

• "Tell me about a time you had to work with a difficult team member."
• "Describe a situation where you had to deliver bad news to a client or stakeholder."
• "Give an example of when you had to learn something quickly to solve a problem."
• "Why EY specifically, and which service line interests you most?"

A generic "I want to do consulting" answer gives the interviewer little evidence of fit. Specify the service line and connect it to the work. For example, explain why evaluating deals through both commercial and financial lenses appeals to you.

For a complete behavioral prep guide, see behavioral interview consulting and case interview fit questions.

The Group Case Exercise: How to Stand Out

Candidate reports describe group, written, and presentation exercises in some EY processes, with widely varying group size, preparation time, presentation length, and advance notice. If your invitation confirms one, use its instructions as the format source of truth and practice both the analytical task and collaborative delivery.

Useful behaviors to rehearse if a group exercise is confirmed:

• Do you contribute analytical insights (not just opinions)?
• Do you build on others' ideas rather than competing?
• Can you disagree constructively without shutting others down?
• Do you help the group stay on track when time runs low?

Tactical advice:

• Volunteer to structure the initial approach, but do not dominate the conversation
• When another candidate makes a good point, build on it explicitly and connect it to the group's decision.
• Track time for the group: "We have 20 minutes left, and we haven't discussed risks yet." This is a leadership signal that does not require arguing.

Readiness-Based EY Case Interview Prep Plan

Execution checklist

• ✓

  Identify which EY service line and role you are targeting. The work focus determines useful practice themes; the invitation determines the actual exercise.

• ✓

  Practice both guided and open cases until the format is confirmed. Candidate reports describe both, so flexible structure and clear responses reduce format risk.

• ✓

  Review basic valuation concepts (multiples, synergies, DCF logic). S&T and Parthenon cases frequently involve acquisition evaluation. You cannot fake financial intuition.

• ✓

  Prepare your 'Why EY?' answer with division-specific detail. Generic answers about consulting are immediately obvious. Reference the specific practice area and type of work.

• ✓

  Run a group or presentation simulation if your invitation confirms one. These exercises appear in some, but not all, EY processes and require different preparation.

• ✓

  Verify the current role and invitation details. Official instructions outrank candidate reports for the format, timing, and required exercises

Common Mistakes by Division

EY Consulting applicants:

• Assuming every EY Consulting case is interviewer-led. Practice both guided responses and open structure until your format is confirmed.
• Ignoring technology, operations, and implementation trade-offs that are relevant to the service line's published work.
• Preparing only case mechanics and no evidence-backed collaboration or stakeholder story.

EY S&T applicants:

• Not understanding basic deal mechanics. If the role includes transaction work, practice calculating an EBITDA multiple and explaining revenue and cost synergies before the interview.
• Treating S&T cases like banking technicals. They want strategic reasoning, not just financial modeling.
• Treating S&T and EY-Parthenon as interchangeable instead of checking the actual role description and work focus.

EY-Parthenon applicants:

• Preparing only for broad Big 4 consulting cases when Parthenon often expects strategy-style casing. See the full EY-Parthenon case interview guide for specific prep.
• Skipping written or presentation practice after your invitation has confirmed that component.
• Generic "Why EY" answers that do not reference Parthenon's PE practice or strategy focus

Related Guides

• EY-Parthenon case interview guide: deep dive on EY's strategy arm, written case, and PE-focused prep
• EY Launch internship program: EY's early-career and student leadership pipeline into full-time consulting roles
• Deloitte case interview guide: Big 4 peer with a comparable interview format
• KPMG case interview guide: Big 4 peer comparison for candidates applying across firms
• PwC case interview guide: Big 4 peer including written case and group formats
• Case interview frameworks complete guide: how to build structures for any case type
• Profitability framework: financial decomposition skills that transfer to S&T and Parthenon cases
• EY cover letter guide: how to tailor your application letter to EY's practices and values before the interview stage

Sources and Further Reading (checked July 20, 2026)

• Management Consulted, EY Interview Guide: https://managementconsulted.com/ey-interview/
• MConsultingPrep, EY Case Interview: https://mconsultingprep.com/ey-case-interview
• My Consulting Offer, EY Case Interview: https://www.myconsultingoffer.org/case-study-interview-prep/ey-case-interview-parthenon/
• My Consulting Offer, EY Online Assessment and Job Simulation: https://www.myconsultingoffer.org/case-study-interview-prep/ey-online-assessment/
• IGotAnOffer, EY-Parthenon Case Interview: https://igotanoffer.com/blogs/mckinsey-case-interview-blog/ey-parthenon-case-interview
• Glassdoor, EY Interview Questions: https://www.glassdoor.com/Interview/EY-Interview-Questions-E2784.htm
• Glassdoor, EY Consulting Interview Questions: https://www.glassdoor.com/Interview/EY-Consulting-Interview-Questions-EI_IE2784.0,2_KO3,13.htm
• EY Careers FAQ: https://www.ey.com/en_us/careers/frequently-asked-questions
• Umbrex, EY Consulting Profile: https://umbrex.com/resources/profiles-of-the-top-consulting-firms/overview-profile-history-ey-consulting/