After signing the offer with McKinsey and During the certn background check I inputted 1 month while the certificate of my internship said 2 months because they calculated the whole period full time and part time while I registered the full time only and the ceo got the email and confirmed that my period was that of which I registered (one month), so is this serious or what. I already submitted the certificate in the collection of data phase.
Background check date discrepancy at McKinsey
Hey Battal!
A small date mismatch like 1 vs. 2 months in a McKinsey background check is not serious at all. These differences happen constantly when part‑time and full‑time periods are counted differently. In your case, you even under‑reported, your certificate already shows the full period, and the CEO confirmed the dates you entered, that’s exactly the kind of harmless administrative inconsistency HR sees every week. McKinsey only cares about verifying that the job and degree are real, not about minor timeline variations. This won’t affect your offer.
Alessa
Take a breath. This is recoverable.
This is a low-severity discrepancy, not a fraud issue. The certificate covers your full duration including part-time, while you entered just the full-time portion on Certn. The CEO confirmed your version. That matters a lot.
What to do now. Be proactive. Drop your McKinsey HR a short note flagging it before they spot it themselves. Something like, "wanted to flag a small discrepancy, I entered 1 month reflecting the full-time portion. The certificate shows 2 months because it includes the initial part-time period. The CEO has confirmed my version directly."
Keep the CEO email saved as backup. Don't ignore it hoping they won't notice.
You'll be fine.
Good luck.
Hey,
Let me try to unpack, because I am not 100% sure I understand your message. If I understand correctly, you wrote on your resume that the internship lasted 1 month, while in reality it was 2 months? If that's the case, I see no issue. You can always say you were being conservative and did not include the part-time portion of that internship
Problems arise when you pretend you worked more than you did in reality (and typically when the discrepancy is larger), not the opposite :)
Best,
Tom
you have nothing to worry about