Cash Bar

Cash Bar

A beverage-service system where guests/attendees pay for their drinks is known as a cash bar.

Don't even think about suggesting a cash bar as an option for a wedding (unless you're in the UK where, apparently, wedding guests are accustomed to paying for their drinks at private social events)!

A cash bar will catch most US wedding guests off-guard. Instead, suggest that your clients serve a signature cocktail or beer and wine, only.

The opposite of a cash bar is an open bar.

Merriam-Webster Online Dictionary
cash bar (noun)
a bar (as at a reception) at which drinks are sold - compare open bar
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