There are no state or federal laws preventing you from carrying at your local bank. As far as which banks are "anti-gun", you would have to check with your local banks individually. I have OC'ed at my local bank numerous times without incident. But, I live in a small community, have been banking at the same bank for years, and they all know me. If you are a business owner and you have large deposits, I recommend you OC until someone says something. If they ask you to take your gun outside, then comply with their request, then march right back in there and kindly tell the bank manager why you will be taking your business and your money elsewhere. Then ask him to close your account immediately. If he changes his mind, you have won a new convert. If not, then another bank has just won your business.