California became the first to require that credit card companies create a four-digit unique code for firearms stores this month. On the same date as the California law went into effect, July 1, Tennessee, Georgia Iowa, and Wyoming also passed laws prohibiting the code.

The code is known as the Merchant Category Code (MCC) and tracks the type business that made the transaction to determine such things as tax reporting or transaction fee. The code can be used to track buying behavior but does not include specific purchases.

A non-profit organization that promotes international standards paved the road for credit card companies to create a code for gun retailers by 2022. Since then, state legislators have taken opposing positions to encourage or prevent credit card companies to use the codes.

Colorado passed a similar law to California’s in this year. Gun safety advocates applauded the move. In the meantime, more than 15 states have passed laws banning MCCs. Many of these have already been signed into law.

Take a look at how states differ in their approach to MCCs.

Legislative whiplash after international approval of gun store code

Reuters reported that the International Organization for Standardization has approved the creation of a code for firearm retailers called a “merchant code code” (MCC) in 2022. These codes allow businesses to be classified according to the types of products they sell. The codes can be used to determine how a purchase is processed by financial institutions, but do not identify the specific items that were purchased.

MCC codes are available for a variety of items and industries. Visa, for example, outlines MCC coded for veterinary services and airlines.

In a letter signed by fourteen U.S. lawmakers, the legislators who support gun reform backed the new code. They also called on the Department of the Treasury to issue guidance to financial institutions in order to implement the code. Senators such as Sen. Elizabeth Warren (D-Mass. and Sen. Kirsten Gillibrand, D-N.Y. They claimed that the codes would help financial institutions identify illegal purchases, flagging them to law-enforcement before tragedies like those at Robb Elementary in Uvalde (Texas) occur.

California, as of July 1, will require California’s four major credit card companies to implement the code. Initially, they announced their plans to use it, but then backed out in March 2023 due to legislative blockages in various states. Visa Merchant Data Standards Manual confirms that MCC5723 is in effect as of July 1, according to the Visa Merchant Data Standards Manual.

The National Rifle Association Institute for Legislative Action is partially responsible for encouraging lawmakers to pass state bans.

California, Colorado, New York pass gun retailer MCC requirements

In September 2023, California Gov. Gavin Newsom has signed AB 1587 which mandates that banks and credit card companies implement the MCC in California for gun dealers, according to a release by the bill’s sponsors.

Payment institutions had to create the MCC code by July 1, 2020 and assign it to merchants before May 25, 2025.

Colorado Gov. Jared Polis, the Colorado Governor, signed a similar law in May that required MCCs from gun sellers. However, it only applied to businesses within Colorado. The bill is scheduled to take effect on August 7, 2024. The Colorado bill’s supporters cited a 2012 shooting in a movie theatre in Aurora, which killed 12 and injured 60. The Fort Collins Coloradoan (part of USA TODAY Network) reported that the shooter used a MasterCard in the six weeks leading up to his shooting to buy $11,000 of weapons and equipment.

Gun violence prevention groups Brady & Guns Down America applauded Colorado’s new bill.

New York State Senate passed a similar bill at the end of 2024’s legislative session. New York Gov. Kathy Hochul’s office told USA TODAY in an email that she would review legislation but had not indicated if she planned to sign it.

NRA urges lawmakers to address MCC; 16 bills signed

According to the Firearm Industry Trade Association, 16 states have passed laws that prohibit assigning MCCs to gun retailers. These include:

Florida – Effective January 1, 2023

Idaho – Effective January 1, 2023

North Dakota – Signed by Governor on April 29, 2023

West Virginia – Effective June 8, 2023

Texas – Effective Sept. 1, 2023

Montana – Effective October 1, 2023

Mississippi – Effective Jan. 1, 2024

Utah – Effective May 1, 2024

Iowa – Effective July 1, 2024

Wyoming – Effective 1 July 2024

Tennessee – Effective 1 July 2024

Georgia – Effective 1 July 2024

Louisiana – Effective, Aug. 1 2024

Indiana – Effective Oct, 1, 2024

Alabama – Effective October 1, 2024

Kentucky – Effective Jan. 1, 2025

New Hampshire, Ohio and at least one chamber of the New Hampshire legislature have passed similar bills.

Several of these laws are known as “Second Amendment Privacy Acts” or “Second Amendment Financial Privacy Acts” informally. The NRA and NSSF both praised the majority of the new laws.

Jeff Landry signing SB 301, the most recent of these bills to receive state executive approval, the NSSF said in a press release: In response to Louisiana Gov.

This NSSF-supported bill protects sensitive financial and personal information for people who purchase firearms and ammo in The Pelican State ….The Second Amendment Financial Privacy Act was designed to prevent the misuse of private and lawful firearm and ammunition purchases by politicians.

Iowa, Wyoming, and Georgia all issued similar statements.

Visa and Mastercard have told The Tennessean (part of USA TODAY Network) that they only use the code where required by law.