Even though you are legal, your current ID might cause issues:
In many jurisdictions, driver’s licenses expire on your 21st birthday. An expired ID is not a valid form of identification for purchasing alcohol. can you buy alcohol on your 21st birthday
Some bars operate on a "business day" model and may not recognize your new age until they reopen for a new shift later that day. Even though you are legal, your current ID
Many states issue vertical IDs to minors. While these remain legally valid until they expire, some scanners or cautious bouncers may reject them simply because of the format. Even though you are legal
Private businesses—including bars, liquor stores, and restaurants—have the legal right to refuse service for non-discriminatory reasons. Can I buy alcohol with an under 21 license on my birthday?