A new law requiring New York businesses to clearly display the total cost of purchasing items with a credit card — including any surcharges — is in full swing.

As of Sunday, businesses in the Empire State are required to disclose any additional credit card surcharges before a customer begins to check out.

The businesses can either post the total price, inclusive of the credit card surcharges, or list the different prices for both card and cash payments for items.

“As more New Yorkers use credit cards and EBT [electronic benefit transfer] products to purchase goods and services, pricing transparency is critical for consumers to make informed decisions at the register,” state Sen. Jeremy Cooney (D-Rochester), who helped spearhead the legislation, told The Post.

“My legislation was designed to help people better understand the total cost — not just a processing fee percentage — and to be protected from surprise fees at checkout.”

The law, which was signed by Gov. Kathy Hochul in December, also prevents shop owners from charging customers more in credit card surcharges than what the business is charged by the processing companies.

Under the new requirements, businesses can’t simply post a sign on the door, or at the register, stating that there is an additional 3.9% surcharge for credit cards.

They have to clearly spell out how much the additional percentage will set the customer back, meaning the businesses can’t have a price tag saying: “$10.00, + 4 percent if paying with a credit card.”

“New Yorkers should never have to deal with hidden credit card costs, and this law will ensure individuals can trust that their purchases will not result in surprise surcharges,” Hochul said in a statement last week as she warned of the upcoming changes.

“Transparency is crucial in building trust between businesses and communities and now patrons will be empowered to budget accordingly.”

The law doesn’t apply to debit cards.