Gun owners are now required to report loss, theft, destruction, sale or transfer of a firearm to the Chicago Police Department and the Cook County Sheriff's office.
Violators face six months in jail.
"I'm very open to any type of reform or change that deals with preventing criminals from getting access to handguns," said Mayor Rahm Emanuel, "or making sure people, when they own a gun, are responsible in the same way that they are for a car."
Anyone found in possession of a firearm without a permit will face up to six months in prison.
