Is it a criminal offense in OH to ignore a no guns sign on a business or can the owner just ask you to leave the premises if caught?  What about hotels?

I am not a lawyer but I stayed at a Holiday Inn Express.

My understanding is criminal trespass happens only when you see the sign and ignore it, or (a) you did not see the sign, and (b) you are asked to leave, and (c) you do not leave.

It applies to any business, including hotels, but only applies to concealed carry. It does not apply to keeping a firearm in your room.

I’ve never seen the sign at any hotel except a lodge at an Ohio state park.

This opinion is worth what you paid.

Buckeye Firearms Association has more thorough description of the law.

What sign ?

I think THIS may apply to the majority, but me personally, I obey all laws......

Thanks guys.  I'm in Cleveland now and no, the hotel was not posted.

Actually in Cleveland?  Unless you are carrying concealed without a license, the most that should happen is the establishment asks you to leave.  If you don't, or return, then you are committing a misdemeanor.  I say "should" because you can't count out an asshole, who just makes up laws, giving you a hard time.

If you knowingly carry in a posted premises, that is a different matter.  "Knowingly" is key, because it is difficult to prove that you knew it was posted.  As oblivious as people are, it is entirely plausible that you can miss a sign.  Since you say they haven't posted anything, there really isn't anything to worry about.

Here is the ORC section relating to this aspect of concealed carry, if you are bored:

https://codes.ohio.gov/ohio-revised-code/section-2923.126

I have also found that as I get older I need reading glasses to make out the fine print on all of those signs. Unfortunately my readers are usually in my pocket. Bummer.

I’m an Ohio cop.

As a practical matter, unless you are in one of the places prohibited by statute (which is a no-no) just quickly apologize and leave if confronted or asked by the business or property owner.

If the police have to come because you didn’t leave when asked, you may be issued a summons or have some other negative experience.

Basically, don’t be a dick and you’ll likely be just fine.

This, at least 99% of law enforcement in the state aren't going to charge you with trespass if you leave the first time you're asked.  Don't argue, just leave.