New York
State Regulations
There are no regulations in the state of New York that prohibits a merchant from offering a cash discount to a customer to encourage that customer to pay by cash or similar means instead of a credit card for purchasing services or goods.
(3) The NY Court of Appeals concluded that if a merchant posts its prices and charges lower prices to cash customers, it must post the price charged to credit card customers. As a result, the court also concluded that the law prohibits a merchant from using a “single-sticker-price” scheme in which a merchant posts a single cash price for its goods and services but indicates an additional amount is added for credit card customers. See link