BYOB

BYOB or BYO is an initialism meant to stand for "bring your own booze", "bring your own bottle", "bring your own beer" or "bring your own beverage".

BYOB is often placed on an invitation to indicate that the host will not be providing alcohol and that guests are welcome to bring their own. Some business establishments allow patrons to bring their own bottle, sometimes subject to fees or membership conditions, or because the establishment itself does not have license to sell alcohol.