In most states, gun magazines can be purchased without a license. However, there are a few states that require a license to purchase or possess a gun magazine. Some of these states include California, Colorado, Connecticut, Hawaii, Maryland, Massachusetts, and New Jersey. Some municipalities require a license to purchase or possess a gun magazine. For example, in New York City, individuals must have a firearms dealer license to purchase a gun magazine.
Typically, you will not need a license to purchase a gun magazine if you are buying it for personal use. However, if you are purchasing multiple magazines or selling them, you may need to obtain a license depending on the state laws. It is always best to check with your local law enforcement agency to determine the laws in your area.