"E&Y (alt) Marriott code 253511 is a secondary Ernst & Young code, alongside the primary EYC code. Fishbowl posts from Big 4 staff: "How do I use the Acc or E&Y codes at Marriott and get around the ID check piece?" — confirming that consulting firm ID checks are a well-known friction point. The same risk profile applies to secondary codes: US select-service essentially never checks; US full-service 10-20%; international meaningfully higher. EY (Ernst & Young) branded itself as EY globally in 2013 — some properties may still see "Ernst & Young" in the code description."

"I occasionally try to get the corporate rate for a company I'm visiting in the area (for sales/consulting). Only once has a front desk clerk asked me to prove my eligibility, and she was satisfied by me giving the name and telephone number of the person I was visiting."

"I think the generic 'show corp id' designation means show the company business card. I think a lot of us don't have them or, if we do & we're not going to an office that we'd need to show them, leave them at home. I worked for some F500s that didn't require corp ids with shiny smiling faces on them & others that did; same with company credit cards. All, however, provided biz cards when working for them."