The legislation Gov. Pat Quinn signed Wednesday requires shelters to scan twice for microchips. The first scan would be within 24 hours of the animal's arrival and a second scan before it's adopted, transferred or euthanized.
Shelters also are required to reach out to the person registered with the animal's microchip by phone or email. Currently they only need to send a letter, a process that can be ineffective if the owner has moved.
Quinn says pets are part of people's families and the state wants to do everything possible to reunite lost animals with their owners.
Quinn's own dog, Bailey, recently died.
The law goes into effect Jan. 1.