BCG Online Assessment Guide

BCG candidates have reported assessment invitations arriving 30 to 90 minutes after submitting an application, with 48 hours to complete. That timing detail matters more than any practice question, because it means the BCG online assessment isn't a stage you prepare for after applying. It's a test you either walk in ready for or fail on logistics.

At WSG I watch strong candidates get filtered out of BCG's process every cycle at exactly this step, usually because they treated the chatbot as a formality. This guide covers what the assessment is, how the Casey chat format works, what's known and unknown about scoring, and the preparation that fits into the window before you hit submit.

What is the BCG online assessment?

The BCG online assessment is a chat-based case simulation, widely known as the Casey chatbot, that most BCG offices use to screen candidates before human interviews. Candidates work through one business case in roughly 25 to 35 minutes, answering around 8 to 10 questions of mixed formats, and finish by recording a short video recommendation. In some BCG markets, this is called the Online Case Experience (OCE) and is guided by Casey, a chatbot.

So don't prepare for “the Casey test” as if it were one universal BCG assessment. The exact sequence and format vary by office and recruiting process. The safe preparation strategy is to be ready for both: structured problem-solving on the CCA and a case-style business problem on the online case.

Can you retake the BCG online assessment?

Do not assume you will get a second attempt. BCG’s current U.S. recruiting materials say that candidates who have previously completed the Online Case generally will not be prompted to take it again; BCG will use the previous submission in the application review. The policy can vary by recruiting program. For example, BCG currently tells some MBA candidates that retaking the Online Case from a previous application is optional, while candidates applying to certain international offices may be asked to retake it. The CCA is stricter: BCG states that candidates who have already taken the CCA generally will not take it again, with a new CCA required only if more than a year has passed.

Bottom line: treat every assessment as if it is your only shot. Don't rely on a retake, and don't make your application plan assuming you can improve your score later.

What BCG is screening for

Start from the firm's side. BCG receives enormous applicant volumes and can't put humans in front of most of them, so the assessment does the first case interview at scale. BCG's own preparation guidance says its case assessments measure structuring, asking thoughtful questions, analyzing data, performing quick calculations, and communicating clearly, and stresses that there isn't always a single right answer: the approach is what's being judged.

That framing should change how you play it. Casey isn't a trivia quiz where you either know answers or don't. It's a compressed case interview where partial credit lives in your reasoning, especially in the free-text responses. Answer the chatbot the way you'd talk to a live interviewer: structure first, then the number, then what it means.

The format, in detail

Everything below comes from consistent candidate reports rather than official BCG documentation, so expect variation by office and cycle

• One business case, threaded through a chat interface with Casey.

• Roughly 8 to 10 questions across 25 to 35 minutes, individually timed.

• Question formats: single and multi-select multiple choice, numeric entry, short and long free-text, and chart or exhibit interpretation.

• A signature opener: pick the three or four most relevant data sources from a list of about eight, testing prioritization before analysis.

• Calculators are allowed, and the math is calibrated accordingly: harder than live-interview arithmetic.

• Strictly one-way: no pausing, no backtracking, answers final.

• The finale: about one minute of prep, then a one-take recorded video giving your recommendation.

The chat format changes the experience more than candidates expect. There's no interviewer to read, no partial-credit nodding, and no chance to ask clarifying questions mid-stream. The case simply advances. Candidates who practice only live casing report the silence as the strangest part.

The timing trap, and where the assessment sits

The assessment arrives at the very front of the process, functioning as a round zero after the resume screen, and some offices send it to effectively all applicants while others use it more selectively. International processes can look different. For example, BCG’s Australia/New Zealand process sends the online case after the application and uses it as part of the screening process before moving candidates to another assessment and then interviews.  You may see prep sites estimate that only 20–30% of candidates advance past the assessment, but BCG does not publish an official pass rate. Treat those numbers as directional, not fact.

Combine that with the reported 30-to-90-minute invite and the 48-hour window, and the planning rule writes itself: finish your assessment preparation before you submit the BCG application, because the test can arrive the same afternoon. The 48 hours is for scheduling a quiet sitting, not for learning case math.

For the current calendar: BCG closed Summer 2027 internship applications after its June 2, 2026 deadline with no fall round, so the next undergrad window arrives with the following cycle, expected to open in spring. Sophomores have separate doors, including BCG's Growing Future Leaders program, which runs its own process.

How Casey is graded, and where the guesswork starts

Here's where a credible guide has to admit the limits of what's known. BCG doesn't disclose scoring. Prep sites conflict: one widely-cited claim describes plus-three for correct and minus-one for incorrect answers, while other reporting finds no evidence of wrong-answer penalties. Nobody outside BCG can settle it 

What the reports agree on is more useful. Multiple-choice and numeric answers are graded on correctness. Free-text answers are graded on the quality of structure and reasoning, not keyword matching. And the video recommendation is reviewed as a communication sample. The practical strategy that follows: never leave a free-text box thin. Two structured sentences with a driver and a number beat a one-word answer even when the one word is right.

And since guessing penalties are unproven either way, answer everything. An unanswered question scores zero with certainty.

How to prepare, in order of return

First, get case-fluent in the normal way, because Casey is a case interview wearing a chat interface. Profit trees, market sizing, chart reading, and hypothesis-first thinking all transfer directly. If you're already preparing for live MBB interviews, roughly 80 percent of the work is done.

Second, practice in the actual format. BCG publishes an official interactive practice case, the Climate Case Challenge, which is the closest free approximation of the chat experience, and its case preparation page sets out what the firm says it measures. Run the practice case twice: once untimed to learn the rhythm, once timed to feel the pressure.

Third, drill the two skills the format uniquely stresses. Timed chart interpretation: pull exhibits from any case book and give yourself 90 seconds to extract the "so what." And calculator-speed arithmetic: the math allows a calculator, so the differentiator becomes setup speed, knowing which numbers to multiply before your fingers move.

Fourth, rehearse the data-source opener. The pick-the-relevant-sources question rewards a habit most students never build: asking "what would I need to know to answer this" before touching any data. Practice by reading a case prompt and listing your top three information requests before reading on.

The video question deserves its own rehearsal

One minute of prep, one take, no do-over. The video recommendation fails candidates who are fine at casing and unpracticed at concluding.

Build the 60-second synthesis as a repeatable shape: recommendation in the first sentence, two supporting reasons with a number each, one risk with how you'd manage it, stop talking. That shape is rehearsable tonight. Record yourself on a laptop answering "should our client enter this market" for any practice case you've done, watch it back once, and fix the single worst thing. Three reps of that loop outperforms an hour of reading about the video question.

Say this, don't say that, in the video answer.

Don't say: "There are several factors to consider on both sides, and it depends on the client's priorities."

Say: "I recommend entering the market. First, it's growing 12 percent annually with no dominant incumbent. Second, our client's existing distribution covers 70 percent of target customers. The main risk is price competition, which I'd manage by launching in the premium segment first."

In free-text answers.

Don't say: "Revenue could be increased through better marketing."

Say: "Revenue is price times volume. Volume looks capped by store traffic, so I'd test a 5 percent price increase in the two highest-loyalty regions first."

If the invite already landed: the 48-hour plan

Some readers arrive at this guide with the clock already running, so here's the triage version.

Hour one: schedule the sitting for tomorrow, not tonight, in a quiet room with a charged laptop, a calculator, scratch paper, and a stable connection. Hours two through four: run BCG's Climate Case Challenge once untimed and once timed, which teaches the chat rhythm faster than any article. Hour five: drill arithmetic setup with a calculator, ten problems of the percentage-and-breakeven variety, answers spoken aloud. Hour six: rehearse the 60-second video synthesis twice on camera using any case you know. Then stop preparing and sleep, because a rested candidate beats a crammed one on a test where every question is timed.

Skip entirely: framework memorization, forum doom-threads about pass rates, and any paid crash course sold on urgency. The test measures thinking speed and structure, and 48 hours only has room to sharpen what exists.

With 48 hours' notice, one practice case in the real format plus math and video reps beats every other use of the time.

If your invite doesn't mention Casey

BCG's screening varies by geography, which surprises candidates comparing notes across borders. Reports through 2026: German-speaking offices use a 30-minute cognitive-style test, the UK runs a shorter numerical assessment, and US and Canada Associate candidates sit the Consulting Career Assessment that wraps the online case, while the old Potential Test is fully retired and Pymetrics survives only as a legacy step in scattered processes . The U.S. process is different again. U.S. candidates receive the Consultant Career Assessment (CCA) shortly after applying, and selected candidates may then complete a separate online case. For U.S. and Canadian recruiting, BCG's current materials make clear that the assessment sequence depends on the office and application.. Read your specific invitation email carefully and prepare for the test it names, not the one your friend took in a different office.

The whole guide compresses into a sequence. Get case-fluent first. Run BCG's own practice case twice. Drill charts, calculator setup, and the 60-second video synthesis. Then, and only then, submit the application, with a quiet 45-minute window reserved within the next two days. The assessment rewards candidates who respected it enough to prepare and punishes everyone who assumed a chatbot couldn't be the real interview. It is the real interview. Treat it that way and round one usually follows.