Can I go to a bar in NYC without drinking at the age of 20

Euro, I'm fairly certain the actual legal answer to your question is

yes, as a matter of law it's completely OK, legal in NY State to go in to a place which sells alcoholic drinks, if you are under 21 and you don't actually drink alcohol.

Note that - of course - some/many establishments have a sign "21 and up only" or "25 and up only" or "tall redheaded 40 year old people only" or whatever, that has no connection at all to alcohol laws. To be clear it's perfectly legal for bars in NY to discriminate (so to speak) against under 21s.

Note however, putting aside the law, we need a current New Yorker on here to tell us how common it is that bars/nightclubs simply do not allow under 21s.

Note that if you're thinking "cool nightclubs" (aside - why go to NY? you're 70 years old?! :) it's not the 60s anymore) they do (although this can change rapidly) often allow only over-some-high-age because it's just too inconvenient for the bar staff to check everyone. (Indeed, conversely back the 90s a "trendy" thing was actually all-night nightclubs catering specifically to youngsters, like 13 etc, obviously with no alcohol at all sold.)

BTW not specifically an answer to your legal question but you can easily google up articles such as

http://guestofaguest.com/new-york/nightlife/no-id-required-the-21-best-spots-to-party-if-youre-under-21

http://www.amny.com/things-to-do/underage-in-nyc-here-s-where-to-party-1.9180970

A recent article from the local TV station

http://newyork.cbslocal.com/top-lists/best-nightlife-spots-for-the-under-21-crowd-in-new-york/

Technically they won't allow you in, but many bars don't card at the door. If they're popular enough (but not popular enough to have a door guy), you'll be able to get in without anyone checking or noticing. In these cases, they'll just card you at the bar when you order a drink. I don't drink much but hang out with friends at bars somewhat frequently, I'd say I get carded at the door 50% of the time. We like quieter, more beer-bar oriented places though. There's no way to say "this place you'll be able to get in, this place you won't", you just have to walk around and try, it depends on the night.

Note that you'll definitely be able to get into many concert venues, DIY spaces, etc., which almost universally do check ID, but frequently admit all-ages. They just won't give you the wristband or stamp that totally securely authenticates you as 100% ?21, no way to fake that. Silent Barn is an example.

It's astounding nobody has any actual legal info on the simple question, can you enter a bar if you're under 21/18/whatever in New York State.

Here's the closest I've found:

https://www.expertlaw.com/forums/showthread.php?t=101719

"The age at which a person not yet of legal drinking age may enter a bar is up to the owner of the bar."

"While it is illegal to enter a bar if you are under 18.."

There you have it - facts from, um, someone who looks like they might possibly be in the legal profession.

I'm actually very surprised there's actually a law that you cannot go in a bar under 18. I think that may be incorrect.

Conversely I've seen other references that (by the actual law) you can't go to a bar in NYS if you are under 16, but you can if accompanied by an adult.

Fascinatingly, if you google there are many many people asking the identical question asked here. The closest I've found to an actual legal opinion is the one I quote above. But all the answers are just guesses, as on this page.